A data positioning method of determining a position (L1, L2) for designating a portion of data included in a series of pieces of data (WD, WD1, WD2) which have values varying along a predetermined direction, the data positioning method comprising: displaying a plurality of display regions (22a, 22b) on a display device, wherein each of the plurality of display regions corresponds to the predetermined direction and is provided for designating a cut-out position of the displayed series of pieces of data in the predetermined direction; displaying the series of pieces of data in a waveform display region among the plurality of regions; designating a position (PI, P2) by an operation of an operation unit in any region among the plurality of display regions (22a, 22a1, 22a2, 22b, 22b1, 22b2, 22b3) on the display device; obtaining positional information indicating the position (P1, P2) which is designated by the operation of the operation unit, by using a pointing device such as a mouse that determines a position by moving a pointer on a display screen, or a touch panel that determines a position by bringing a finger, an operation member, or the like into contact with a display screen to thereby determine a position; and determining the position for designating the portion of data corresponding to the obtained positional information, characterized in that the plurality of display regions include at least one region (22b, 22b1, 22b2, 22b3) for designating a plurality of discrete positions (MK, MK1, MK2, MK3) of the displayed series of pieces of data in the predetermined direction, and wherein any one position is determined among the plurality of discrete positions (MK, MK1, MK2, MK3) when the position in the at least one region (22b, 22b1, 22b2, 22b3) for designating the discrete positions (MK, MK1, MK2, MK3) is designated and the positional information indicating the position in the at least one region (22b, 22b1, 22b2, 22b3) for designating the discrete positions (MK, MK1, MK2, MK3) is obtained. displaying a plurality of display regions (22a, 22b) on a display device, wherein each of the plurality of display regions corresponds to the predetermined direction and is provided for designating a cut-out position of the displayed series of pieces of data in the predetermined direction; displaying the series of pieces of data in a waveform display region among the plurality of regions; designating a position (PI, P2) by an operation of an operation unit in any region among the plurality of display regions (22a, 22a1, 22a2, 22b, 22b1, 22b2, 22b3) on the display device; obtaining positional information indicating the position (P1, P2) which is designated by the operation of the operation unit, by using a pointing device such as a mouse that determines a position by moving a pointer on a display screen, or a touch panel that determines a position by bringing a finger, an operation member, or the like into contact with a display screen to thereby determine a position; and determining the position for designating the portion of data corresponding to the obtained positional information, characterized in that the plurality of display regions include at least one region (22b, 22b1, 22b2, 22b3) for designating a plurality of discrete positions (MK, MK1, MK2, MK3) of the displayed series of pieces of data in the predetermined direction, and wherein any one position is determined among the plurality of discrete positions (MK, MK1, MK2, MK3) when the position in the at least one region (22b, 22b1, 22b2, 22b3) for designating the discrete positions (MK, MK1, MK2, MK3) is designated and the positional information indicating the position in the at least one region (22b, 22b1, 22b2, 22b3) for designating the discrete positions (MK, MK1, MK2, MK3) is obtained.