DOI: 10.5061/dryad.2547d7wwz
title: Fruit-shape data of 574 Chinese white olives

description: We digitized the side profiles of 574 fruits of Canarium album (Lour.)
 DC., and used an explicit re-expression of Preston’s equation (referred to
 as EPE hereinafter) to fit the planar coordinates of each fruit profile.
 By using the estimated parameters, we calculated the volume and surface
 area of each fruit. The black_white.zip file saves the black and white
 .bmp images at 600 dpi for the 574 fruit profiles. The edge_data.zip file
 includes the planar coordinates of each of the 574 fruits, and the
 EPE_results.csv file includes the estimated parameters and goodness-of-fit
 of the EPE, and the fruit surface area and volume calculated by the
 surface area and volume formulas of the solid of revolution based on the
 EPE for each fruit. In addition, the EPE_results.csv file also provided
 the measured volumes of 574 fruits using graduated cylinders.
description: 574 <em>Canarium album</em> (Lour.) DC. fruits were
 selected for detailed study. Each fruit was photographed using a
 smartphone (Huawei Nova5Pro, Guangzhou, China), mounted on an adjustable
 tabletop phone mount, while placing the fruit on a metal rack to ensure
 that the mid-line (i.e., the line through the two endpoints on the fruit
 profile) was parallel to the desktop and the surface of the smartphone. To
 calibrate the deviation of the image size of each fruit from its actual
 size, we measured the maximum length of the fruit using a vernier
 caliper. To obtain the planar coordinates of fruit 2D
 profiles, the photographs were converted into black-white images and saved
 as .bmp format using Adobe Photoshop CS2 (version 9.0; Adobe, San Jose,
 CA, USA). A program developed by Shi et al. (2018) and Su et al. (2019)
 developed in Matlab (version &gt;= 2009a; MathWorks, Natick, MA, USA)
 was then used to extract the planar coordinates of each fruit profile from
 the corresponding .bmp black-white image. The function ‘fitEPE’ in the
 package ‘biogeom’ (version 1.3.5) (Shi et al., 2022) in R (version 4.2.1)
 (R Core Team, 2022) was used to estimate the numerical values
 of <em>a</em>, <em>b</em>,
 <em>c</em><sub>1</sub>,
 <em>c</em><sub>2</sub>, and
 <em>c</em><sub>3</sub>. The Nelder-Mead
 optimization method was used to minimize the residual sum of squares (RSS)
 between the observed and predicted <em>Y</em>-values of
 <em>C. album</em> fruit profiles. After obtaining the
 estimated parameters of the EPE, we used the surface area and volume
 equations for the solid of revolution (Narushin et al., 2022) based on the
 EPE to calculate the fruit surface area and volume for each fruit of the
 574 fruits. To compare the predicted volume of a fruit
 with its observed volume, we measured volume by submerging each fruit in
 water in a 250 mL graduated cylinder with a diameter of 4 cm and reading
 the observed volume of displaced water. The results were saved in the
 EPE_results.csv file. The above contents were cited
 from Wang et al. (2023). References
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