Abstract:
Systems and methods are disclosed for displaying a strip chart on an electronic display. A furthest extremum value of the measured quantity is recorded over a period of time and a plurality of values of the measured quantity are displayed on the strip chart. The furthest extremum value is used to automatically rescale the strip chart, providing for at least one bound of the zoomed range. In response to receiving a selection of a zoom factor defining a degree of magnification of the strip chart, the strip chart is automatically scaled to a degree of magnification commensurate with the zoom factor and the strip chart may be automatically scaled such that the strip chart is bounded on one side by one of a furthest extremum maximum or minimum value and the other one of the furthest extremum maximum or minimum value is not displayed on the strip chart.

Description:
RELATED APPLICATIONS 
     This application is a continuation of and claims priority to U.S. application Ser. No. 11/624,151, filed Jan. 17, 2007, which claims priority from U.S. Provisional Application No. 60/760,443, filed Jan. 20, 2006. The entire teachings of each of the above applications are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to the display of measured quantities, and more specifically, but not exclusively, to self-centering bar graph scales and to auto-scaling charts. 
     BACKGROUND INFORMATION 
     Since the beginning of scientific study and research, measuring devices have been developed to help scientists and engineers to advance scientific knowledge and to help them invent. Thus, there has been a need to meaningfully display metrology data for accurate tracking and study of that data for furtherance of scientific pursuit and technological innovation. A bar graph is typically employed to give a better visual representation of a numerical value. Bar graphs are also common on computer displays to indicate the degree of completion of a task, or in contrast, to plot data using a spreadsheet or graphics plotting program. Charts also provide at least a two-dimensional picture of data, which usually is nothing more than a plurality of bar graphs of a first variable charted over a second variable. Thus, bar graphs and other charts may be useful tools with which to analyze any quantifiable data. 
     SUMMARY OF THE DISCLOSURE 
     According to one embodiment, a method for displaying a strip chart on an electronic display comprises recording over a period of time a furthest extremum maximum value of a measured quantity and a furthest extremum minimum value of the measured quantity, receiving a selection of a zoom factor defining a degree of magnification of the strip chart, and, in response to receiving the selection of the zoom factor, displaying, via the electronic display, a plurality of values of the measured quantity on the strip chart, wherein the strip chart is automatically rescaled such that the strip chart is bounded on opposing sides by respective first and second values, the first value comprises one of the furthest extremum maximum value or the furthest extremum minimum value, and the second value is automatically scaled based on the first value and the zoom factor so that the strip chart has a degree of magnification commensurate with the zoom factor and the other one of the furthest extremum maximum value or the furthest extremum minimum value is not displayed on the strip chart. 
     According to another embodiment, a computer-readable medium for use with a measuring device that records over a period of time furthest extremum maximum and minimum values of a measured quantity is provided. The computer-readable medium has instructions stored thereon for displaying a plurality of values of the measured quantity on a strip chart in response to receiving a selection of a zoom factor defining a degree of magnification of the strip chart. The instructions comprise instructions for, in response to receiving the selection of the zoom factor, displaying a plurality of values of the measured quantity on the strip chart, wherein the strip chart is automatically rescaled such that the strip chart is bounded on opposing sides by respective first and second values, the first value comprises one of the furthest extremum maximum value or the furthest extremum minimum value, and the second value is automatically scaled based on the first value and the zoom factor so that the strip chart has a degree of magnification commensurate with the zoom factor and the other one of the furthest extremum maximum value or the furthest extremum minimum value is not displayed on the strip chart. 
     According to yet another embodiment, a system comprises a display configured to display a plurality of values of a measured quantity on a strip chart and a measuring device in operative association with the display. The measuring device is configured to record over a period of time a furthest extremum maximum value of the measured quantity and a furthest extremum minimum value of the measured quantity, receive a selection of a zoom factor defining a degree of magnification of the strip chart, and in response to receiving the selection of the zoom factor, display, via the display, a plurality of values of the measured quantity on the strip chart, wherein the strip chart is automatically scaled to a degree of magnification commensurate with the zoom factor and the strip chart is automatically scaled such that the strip chart is bounded on one side by one of the furthest extremum maximum value or the furthest extremum minimum value and the other one of the furthest extremum maximum value or the furthest extremum minimum value is not displayed on the strip chart. 
     According to still another embodiment, a system is provided for displaying a plurality of values of the measured quantity on a strip chart. The system comprises a means for recording over a period of time a furthest extremum maximum value of a measured quantity and a furthest extremum minimum value of the measured quantity, a means for receiving a selection of a zoom factor defining a degree of magnification of the strip chart, and a means for, in response to receiving the selection of the zoom factor, displaying a plurality of values of the measured quantity on the strip chart, wherein the strip chart is automatically rescaled such that the strip chart is bounded on opposing sides by respective first and second values, the first value comprises one of the furthest extremum maximum value or the furthest extremum minimum value, and the second value is automatically scaled based on the first value and the zoom factor so that the strip chart has a degree of magnification commensurate with the zoom factor and the other one of the furthest extremum maximum value or the furthest extremum minimum value is not displayed on the strip chart. 
     According to yet another embodiment, a method for displaying a strip chart on an electronic display comprises receiving a selection to display a zoomed range of a measured quantity, receiving a selection of a sample number rate, recording over a period of time a furthest extremum value of the measured quantity at the sample number rate, and displaying, via the electronic display, a plurality of values of the measured quantity on the strip chart, wherein the furthest extremum value is used to automatically rescale the strip chart, providing for at least one bound of the zoomed range. 
     According to still another embodiment, a system for displaying a plurality of values of the measured quantity on a strip chart is provided. The system comprises a means for receiving a selection to display a zoomed range of a measured quantity and receiving a selection of a sample number rate, a means for recording over a period of time a furthest extremum value of the measured quantity at the sample number rate, and a means for displaying a plurality of values of the measured quantity on the strip chart, wherein the furthest extremum value is used to automatically rescale the strip chart, providing for at least one bound of the zoomed range. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present embodiments will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that the accompanying drawings depict only typical embodiments and are therefore not to be considered to limit the scope of the disclosure, the embodiments will be described and explained with specificity and detail in reference to the accompanying drawings, herein described. 
         FIGS. 1A and 1B  are embodiments of a graphical display with a bar graph scale showing maximum, minimum, and current values. 
         FIGS. 2A and 2B  are embodiments of a graphical display with a dual bar graph scale, showing auto-ranging and self-centering on the maximum or minimum values, and the current measured value. 
         FIGS. 3A and 3B  are alternative embodiments of the graphical displays shown in  FIGS. 2A and 2B . 
         FIG. 4A  is an embodiment of a basic layout of a current value measurement bar graph juxtaposed with an auto-scaling strip chart. 
         FIG. 4B  includes the bar graph and chart of  FIG. 4A  showing historical display of peak values. 
         FIGS. 5A and 5B  are embodiments of the bar graph and chart of  FIG. 4A  showing the chart&#39;s auto-scaling function. 
         FIGS. 6A ,  6 B,  7 A, and  7 B are embodiments of the bar graph and chart of  FIG. 4A  showing the chart&#39;s zooming function. 
         FIGS. 8A ,  8 B,  9 A, and  9 B are embodiments of the bar graph and chart of  FIG. 4A  showing the chart used as a statistical strip chart. 
         FIG. 10  is a flow chart of an embodiment of a method for providing decisional options to a user of the graphical display of  FIGS. 1A ,  1 B,  3 A, and  3 B. 
         FIG. 11  is a flow chart of an embodiment of a method for providing decisional options to a user of the graphical display of  FIGS. 4A ,  4 B,  5 A,  5 B,  6 A,  6 B,  7 A,  7 B,  8 A,  8 B,  9 A, and  9 B. 
     
    
    
     DETAILED DESCRIPTION 
     The embodiments of this disclosure will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. It will be readily understood that the components of the embodiments as generally described and illustrated in the Figures herein could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of various embodiments, as represented in the Figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of various embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated. In addition, the steps of a method do not necessarily need to be executed in any specific order or even sequentially, unless otherwise specified. 
     As one skilled in the art will appreciate, certain embodiments may be capable of achieving certain advantages over the known prior art, including some or all of the following: (1) zooming in and automatic centering of a measured quantity of interest in a bar graph, thus providing for better resolution of peak values; (2) tracking historical peak values of measured quantities on an auto-scaling chart without need of auxiliary processing, thus providing instant and accurate resolution of a furthest extremum value in a time period; and (3) the ability to track statistical, averaged values of the minimum and maximum peak values of a measured quantity at a user-defined sample number rate over a time period. These and other advantages of various embodiments will be apparent upon reading the following. 
       FIGS. 1A and 1B  are embodiments of a graphical display  100  that may be used on any device or instrument, such as a meter, designed to measure and indicate a quantity, which may include among others, power, voltage, current, resistance, sound energy and frequency, as well as light energy and power such as that which can be measured by an optical meter. The embodiment of the bar graph  102  displayed in both  FIGS. 1A and 1B  includes the current measured value  104  as well as the maximum  106  and minimum  108  values, or peak values, that were once obtained during a current period of measurement. The bar graph  102  may include a scale  110  reflecting a relatively precise indication of the values  104 ,  106 , and  108 . These values may be more accurately represented, to several decimal points or more, through a digital display  112 . The digital display  112  may include the current measured value  104 , the maximum value  106 , and the minimum value  108 . Thus, the bar graph  102  allows simultaneous display of historical peak values  106  and  108 , and the current measurement  104 . 
     Contrasting  FIG. 1A  with  FIG. 1B , it is notable that  FIG. 1B  has a higher current value  104 , which if were to extend beyond the maximum peak value  106 , it would set a new maximum peak value  106 . The differences between the current  104 , maximum  106 , and minimum  108  values may be discerned with differing colors or shades of a color or differing patterns. 
     A user may interact with the graphical display  100  to varying degrees, depending on the application, and a status bar  114  displays what feature may be selected at any given time. The status bar  114  may include a reset  116  of the scale of a meter or other instrument for subsequent tests. The auto-zoom feature  118  is selectable as well, which will be discussed with reference to  FIGS. 2A through 3B . The “show min”  120  and “show max”  122  indicators allow a user to view both maximum  106  and minimum  108  values at once, or to view only one of either the two maximum  106  or minimum  108  values on the bar graph  102 . Thus, displayed in  FIGS. 1A ,  1 B,  3 A, and  3 B are both the maximum  106  and minimum  108  measured values. In contrast,  FIG. 2A  displays only the maximum value  106  while  FIG. 2B  shows only the minimum value  108 . 
     The display of the wavelength  124  of a measured signal may also be included, as may an indicator  126  of the manner with which the measurement range is determined. A measuring device that measures, for instance, optical or electrical power may do so in a series of decade ranges. The user can switch manually between ranges or the user could let the instrument switch automatically based on the actual optical or electrical power read. The indicator  126  thus refers to the choice of auto or manual ranging in measurement, not to the manner in which measured and peak values are displayed. 
     As the difference between a peak value and the current measured value  104  may be very small to miniscule, especially on the larger scale  110  of a metering device, it may be difficult to obtain the desired resolution on a peak value in comparison to a current value  104 . While the numerical display can have any number of significant digits to accommodate the desired resolution, a bar graph  102  is limited by the number of pixels available to the graphical display. In most practical cases, one pixel barely represents a fraction of a percent. Thus, it may be useful to be able to zoom in more closely on a scaled display  102 , thus magnifying that scale to be able to see, in real-time, the on-going variations between the peak values and the current value  104 . In some signal sources that are monitored, these variations are labeled as “noise,” and may have significant interest to an observer. In some cases, the overall peak value, whether the maximum  106  or the minimum  108 , needs to be determined. 
       FIGS. 2A and 2B  are embodiments of a graphical display  200  now using an additional bar graph  202  that may be used to show the zoomed version of the bar graph  102 , centered generally about both the current value  104  and a peak value  106  or  108 , or a point therebetween. A simple zoom bar graph works to a point, but the higher the zoom factor, the quicker the bar of the graph reaches the maximum value it can display and “saturates.” An automatic self-centering algorithm may be implemented to avoid saturation. When the zoomed value reaches the zoom bar&#39;s maximum value on the zoomed scale, new limits are calculated and the “zoom window” is automatically shifted to bring the current value  104  generally centered in the display. 
     Thus, an auto-ranging and self-centering zoomed bar graph  202  may simultaneously display the current value  104  and the maximum value  106  ( FIG. 2A ) to better display the zoomed-in difference between the two, while a bar graph  102  retains a zoomed-out picture of both. The range of the zoomed bar graph  202  may be automatically adjusted to ensure that both a current value  104  and a peak maximum  106  value are still viewable, despite a growing distance due to variability in the measured source. This may be accomplished, for instance, by self-centering the two values  104  and  106  whenever the graph  102  is updated. 
     If the distance between the current value  104  and a peak value  106  or  108  grows so much that to display them simultaneously would require too much zooming out, the auto-ranging aspect of the zoom bar graph  202  may let the current value  104  or the peak value  106  or  108  drop off one end of the bar graph  202  to retain a zoomed focus on the value of interest. The value of interest may be user selectable, and may include the current value  104  or one of a maximum  106  or minimum  108  peak value. As in  FIGS. 1A and 1B , a digital display  112  may display similar data more accurately, showing in  FIG. 2A , for instance, the current measured value  104  and the maximum peak value  106  numerically. 
     Additionally, the above example works the same for a minimum peak value  108  ( FIG. 2B ), for instance, when a user is trying to see the dips in measured quantities with particular interest on the peak minimum value  108 . The auto-ranging, self-centering zoom bar graph  202  may be used to simultaneously display the current value  104  and the minimum value  108  within a zoomed-in range, while a bar graph  102  retains a zoomed-out picture of the two. 
       FIGS. 3A and 3B  are similar embodiments of a graphical display  200  as in  FIGS. 2A and 2B , but with another option available to a user: that of choosing to see both the maximum value  106  and the minimum value  108  on bar graph  102 . That these options are chosen may be highlighted by indicators “show min”  120  and “show max”  122  of the status bar  114 . With such an option, the main bar graph  102  now displays not only the current measured quantity  104 , but also the maximum  106  and minimum  108  values, as discussed with reference to  FIGS. 1A and 1B . The auto-ranging, self-centering zoom bar graph  202  displays, respectively for  FIGS. 3A and 3B , the zoomed versions of the maximum  106  and minimum  108  values, each together with the current value  104 , centered generally within the zoom ranged. 
     An instrument or device with high throughput can take a large amount of data which cannot be viewed in its entirety on a typical display. The user would have to save the data to a large memory for future download or transfer the data at a high rate to a host computer. In either case, the user would have to post-process the data, which requires additional work and cannot be done in real-time with the measurement. As a solution, a user interface may be developed to present the current measurement and the statistical or historical data in real-time in an easy-to-read, graphical format on the same instrument display panel, as shown in  FIGS. 4A through 9B . This obviates the need for separate computing devices. 
       FIG. 4A  displays an embodiment of a graphical display  400 , showing a basic layout of a current-value-measurement bar graph  402 , juxtaposed with an auto-scaling strip chart  404 . A digital scale  406  shows the real-time numerical value of the current value  104 . Also referring to  FIG. 4B , along the right-to-left axis  408  is an indication of magnitude of a measured quantity, while the up-to-down axis  410  is an indication of time, with the most recent measurements lying closest to the top portion of the strip chart  404 , adjacent the bar graph  402 . The total time represented on the strip chart  404  at a given time may be referred to as a “time period.” Along the bottom middle of the strip chart is displayed a zoom factor  412 , which dictates the level of magnification of the chart  404  display. At the bottom right is an updated peak value  414 , a “furthest extremum value,” which is also the chart scale maximum value. This means that despite zooming in on a particular area of historical measurement data, the peak value  414  is continually displayed and automatically used as a full scale of the strip chart  404 . 
     As with  FIGS. 1A to 3B , a status bar  416  may be available to show indication of a user&#39;s selected feature. Such features may include clearing  418  the chart data, for instance, to begin a new measurement period. The strip chart  404  keeps track of the furthest extremum value recorded since the last clear  418  function selection. The furthest extremum value may be the maximum peak value  414 , and the chart  404  is dynamically scaled to this value. This real-time scaling to update the zoom according to a new peak value, is called “auto-scaling,” the results of which are observable in  FIGS. 5A and 5B . As time marches on, the auto-scaling results in the maximum peak value  414  that always falls along the right edge  410 , and the minimum value is resultantly pushed closer to the left edge. This construct, of course, could be flipped where the interest is in a minimum peak value, as will be later discussed. 
     A common application of taking measurement data of a quantity is called “peaking,” in which the user needs to make some adjustments and find the maximum (or minimum) source intensity. Using this type of auto-scaling chart  404 , the user does not have to spot the peak value and memorize it as a target. The visual target is always on the right side (or left side for minimum peaks) of bar graph  402  and strip chart  404 . 
     Another feature of the status bar  416  may include saving the chart  420  to some output format available electronically or in print, for later analysis. An average  422  option is selectable to display the average of maximum  106  and minimum  108  values of measured quantities over time, thus giving statistical average information for a measurement period, which is discussed in more depth with reference to  FIGS. 8A through 9B . Finally, the zoom  424  feature is selectable to zoom in the strip chart  404  to show more detail of the variations of the historical measured peak quantities. 
       FIGS. 6A through 7B  are embodiments of the bar graph  402  and strip chart  404  of  FIG. 4A , showing the chart&#39;s zooming function. As the user visually finds the maximum value, the accuracy of the adjustments is determined in large part by the graphical resolution of the bar graph and the strip chart. To improve this resolution, a zoom function may be implemented in which the maximum peak value  414 , a “furthest extremum value,” is automatically kept as the scale maximum along the right side of the bar graph  402  and strip chart  404 . A scaled minimum value  426 , displayed on the bottom left side is scaled up to achieve the desired zooming factor  412 , thus a minimum value  426  would no longer be the extremum minimum value on strip chart  404 . 
     In the alternative, the roles of the maximum  414  and minimum  426  peak values may switch places when interest is in tracking the furthest extremum minimum value  426  instead. In this case, the maximum peak value  414  displayed on a strip chart  404  may not be the extremum maximum value, but the minimum peak value  426  would always be the extremum minimum peak value, as could be displayed on the left side of the strip chart  404 . 
     For example, the effect of zooming is evident by a comparison of  FIGS. 6A and 6B . In  FIG. 6B , the zooming factor  412  has increased by a factor of around 33 (from 3 to 100), forcing the scale minimum value  426  to 7.5782 from a previous 5.3583. While this zooming truncates the left side of the chart, the magnification becomes adequate for the user to fine tune the adjustment and find the true furthest extremum value  414 . If a user&#39;s interest is in finding the furthest extremum minimum value  426 , the chart may be flipped horizontally so that the right side of the chart  404  is truncated as the zooming factor  412  increases, and the left side of the chart stays scaled to the minimum peak value  426 . 
     In  FIGS. 7A and 7B , increasing the zooming factor  412  further achieves higher levels of magnification, which may reveal details hidden on standard graphical strip charts. Note the variations in dark portions  428  at the right-most section of the graphical data, displaying the noise  428  at different periods of time and to different degrees. For analysis, this sort of graphical data would be resource-consuming to reconstruct on another computer or by post-processing. 
     One of skill in the art will appreciate that the bar graph  402  and strip chart  404  may be configured, along with a user-selectable option, to position the peak minimum value along the right side and the peak maximum value along the left side of the bar graph  402  and strip chart  404  without moving beyond the scope and spirit of this disclosure. Likewise, one of skill in the art would appreciate using both a maximum peak value  414  and a minimum peak value  426  both as “furthest extremum values” so as to bind both sides of the strip chart  404 , in order to track both of them. Although perhaps sacrificing resolution on both the maximum and minimum peaks of the measured values over time, such an option may be viable where the measured source has little variability and an acceptable zoom factor  412  may again be selected by a user. 
     In  FIGS. 8A through 9B  are embodiments  800  of the bar graph  402  and strip chart  404  of  FIG. 4A  showing the chart used as a statistical strip chart  802 . As discussed previously, when a user selects the option to average the maximum  414  and minimum  426  peak values, an indication is reflected as “average”  422  on the status display  416 . The “average”  422  option allows a user to view statistical data of the maximum  414  and minimum  426  peak values of a user-selected number of samples  804 . That is, the user-selected number of samples  804  determines both the statistics window and the rate at which the strip chart  802  is being updated. Each horizontal line shown in the strip chart  802  in  FIGS. 8A through 9B  represents one statistical set of data, or an average maximum value and an average minimum value for the sampled period. 
     If the sample number  804  is set to one, the chart  802  is updated at the maximum rate of measurement, and no effective statistics are presented, as shown in  FIGS. 8A and 9A . When the sample number  804  is increased, however, the strip chart  802  will show the minimum and maximum of each data set, which sets increase with the sample number  804 , as shown in  FIGS. 8B and 9B . The values may be graphically represented by a single line per data set. The line may have two different colors, one for the minimum value and one for the maximum value. This statistics feature may be especially useful in observing short and long-term data variations. An example would include the instance when the data contains a significant amount of noise, as seen in  FIG. 9B . 
     In addition, strip chart  802  may be configured to display in chart form the mean, standard deviation, frequency, and ranges between minimum  106  and maximum  108  peak values. Thus, strip chart  802  may be used to display a wide range of statistical data, and the “averaging” example as shown in  FIGS. 8A through 9B  should be considered exemplary only. Such additional statistical information may likewise be calculated in data sets with which to be displayed over a time period along the chart  802 . The data sets may be calculated through the use of varying algorithms appropriate for the type of statistical data sought, the algorithm also dictating the type of scale used to display the data sets. These algorithms may be developed specifically to match up with a measured quantity, or may be adapted from those already known in the art. 
     One skilled in the art will appreciate that the arrangement of elements on the display of a measuring device can be varied to suit one&#39;s tastes, aesthetic sense, and ergonomic usability, among other factors. For example, the bar graphs and strip charts of  FIGS. 2-9  could be oriented vertically in lieu of horizontally, and fall within the spirit and scope of the disclosure. 
       FIG. 10  is a flow chart of an embodiment of a method  1000  for providing decisional options to a user of graphical displays  100  and  200  of  FIGS. 1A ,  1 B,  3 A, and  3 B. A user may select  1002  to reset the reading of a measuring device, in which case the device will reset  1004  the bar graph(s)  102  and  202  currently being displayed. To “reset” typically means to erase the data being displayed from the bar graph in order to be ready to display another period of measurement of a measured quantity. A user may select  1006  to auto-zoom the bar-graph display  102  or  202 , in which case the device provides  1008  auto-zooming with a second bar-graph, as discussed with reference to  FIGS. 1A through 3B . 
     A user may also select  1010  whether the user wants to display a maximum peak  106  and/or a minimum peak  108  value of a measured quantity. If only one is selected, then displayed  1012  is either the maximum  106  or the minimum  108  peak value on the bar graph  102 , as in  FIGS. 2A and 2B . If both are selected, then displayed  1014  on the bar graph  102  are both maximum  106  and minimum  108  values, as in  FIGS. 1A ,  1 B,  3 A, and  3 B. As a final step, the device translates  1016  whatever measurement values are currently read to the bar graph scale, whether to the bar graph  102  or to the zoomed range of the bar graph  202 , for proper display. 
       FIG. 11  is a flow chart of an embodiment of a method  1100  for providing decisional options to a user of the graphical displays  400  and  800  of  FIGS. 4A through 9B . A user may select  1102  whether to average the incoming data to provide a statistical chart  800 , or whether to zoom into the historical data to see variations in the strip chart  404  peak values. If the user selects to zoom the chart  404 , then the device records  1104  the furthest extremum (or peak) value or values, which may be used to auto-scale the chart. The device displays  1106  the measurement data with at least one peak value, such as the maximum peak shown in  FIGS. 4B to 7B , which may be automatically used as the full chart  400  scale. Note that there may be two furthest extremum values, one a minimum and one a maximum, and the possibility of a zoomed range being between the two, as previously discussed. 
     If a user selects to clear  1108  the measurement data from the display, then the device erases  1110  the display with historical peak values and re-enters the method  1100  at step  1104 , recording  1104  the furthest extremum values and displaying  1106  peak value(s) in an auto-scaling fashion. If a user selects to save  1112  the current chart  400 , then the chart  404  is outputted  1114  to a disk, printer, or other software or hardware recordable medium. A user may also select  1116  a zoom factor  412  with which to adjust the magnification of the graphical data on strip chart  404 . If a user so selects  1116 , then the chart  400  is zoomed in  1118 , bounded with at least one peak as the device auto-scales the chart  400  from either the right or left extremum. This will allow magnification of variations of at least one peak value (i.e. a maximum) while the other peak value (i.e., a minimum) falls off the scale at sufficiently large zoom factors  412 . If a user does not select  1116  a zoom factor  412 , the method  1100  cycles through, having the option to select  1102  average or zoom again. 
     If a user selects  1102  to average instead of to zoom, then incoming peak values are sampled to provide a statistical chart  802  with data points comprising a minimum and maximum value at discrete intervals based on a sample number. Thus, the average minimum and average maximum value for each sampled period is provided. This was also discussed with reference to  FIGS. 8A to 9B . A user may select  1120  the sample number  804 , in which case the device uses  1122  that sample number  804  to generate the statistical strip chart  802 . Otherwise, the device uses  1124  a default sample number. In either case, the device displays  1126  the statistical data at the selected or default sample number rate, until a user either selects  1120  a new sample number, or decides  1102  to select the zooming option. 
     The methods  1000  and  1100  and other methods for generating the displays illustrated and described herein can exist in a variety of forms, both active and inactive. For example, they can exist as one or more software or firmware programs comprised of program instructions in source code, object code, executable code or other formats. Any of the above can be embodied on a computer-readable medium, which include storage devices and signals, in compressed or uncompressed form. Exemplary computer-readable storage devices include conventional computer system RAM (random access memory), ROM (read only memory), EPROM (erasable, programmable ROM), EEPROM (electrically erasable, programmable ROM), flash memory and magnetic or optical disks or tapes. Exemplary computer-readable signals, whether modulated using a carrier or not, are signals that a computer system hosting or running a computer program can be configured to access, including signals downloaded through the Internet or other networks. Concrete examples of the foregoing include distribution of software on a CD ROM or via Internet download. In a sense, the Internet itself, as an abstract entity, is a computer-readable medium. The same is true of computer networks in general. 
     The terms and descriptions used herein are set forth by way of illustration only and are not meant as limitations. Those skilled in the art will recognize that many variations can be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The scope of the invention should therefore be determined only by the following claims (and their equivalents) in which all terms are to be understood in their broadest reasonable sense unless otherwise indicated.