finding an area under a graph

I want to know the area under a graph.

% 
opts = spreadsheetImportOptions("NumVariables", 5);

% Specify sheet and range
opts.Sheet = "Sheet1";
opts.DataRange = "AG4:AK206";

% Specify column names and types
opts.VariableNames = ["PressureMpa6", "PoreDiameter_nm_6", "CumulativePoreVolume_mL_g_6", "SmoothedDV_dlogDPoreVolume_mL_g_6", "x_OfTotalIntrusionVolume6"];
opts.VariableTypes = ["double", "double", "double", "double", "double"];

% Import the data
mean = readtable("/mean.xlsx", opts, "UseExcel", false)

mean = 203x5 table
    PressureMpa6    PoreDiameter_nm_6    CumulativePoreVolume_mL_g_6    SmoothedDV_dlogDPoreVolume_mL_g_6    x_OfTotalIntrusionVolume6
    ____________    _________________    ___________________________    _________________________________    _________________________

      0.001898         5.4695e+05                9.0337e-31                          0.016599                       1.3131e-27        
      0.011365         1.8866e+05                  0.006053                         0.0072507                           8.4375        
      0.020434              98501                 0.0069119                         0.0031069                           9.6935        
      0.032421              44120                 0.0082659                         0.0040477                           11.606        
      0.044323              29301                 0.0089894                         0.0038466                           12.664        
       0.05591              22128                 0.0094183                         0.0037759                           13.287        
      0.067954              17693                 0.0098767                         0.0041917                           13.912        
      0.079652              14780                   0.01016                         0.0040742                           14.323        
      0.091521              12695                  0.010426                         0.0049298                            14.73        
       0.10342              11136                  0.010707                         0.0057902                           15.144        
       0.11537             9908.5                  0.011088                         0.0055884                           15.696        
       0.12714             8926.9                  0.011289                         0.0049494                           15.981        
       0.13882             8123.4                  0.011469                         0.0048232                           16.227        
       0.15053             7453.5                  0.011638                         0.0052111                           16.472        
       0.16213             6888.9                  0.011846                         0.0054966                           16.796        
       0.17398             6398.7                  0.012023                         0.0057163                           17.055        

% Clear temporary variables
clear opts2

figure;
semilogx(mean.PoreDiameter_nm_6(1:103),mean.CumulativePoreVolume_mL_g_6(1:103),XDataSource = 'mean.PoreDiameter_nm_6(1:103)',YDataSource = 'mean.CumulativePoreVolume_mL_g_6(1:103)');
linkdata on;
grid on
xlabel("PoreDiameter_nm_6(1:103)");
ylabel("CumulativePoreVolume_mL_g_6(1:103)");
title("CumulativePoreVolume_mL_g_6(1:103) vs PoreDiameter_nm_6(1:103)");
legend("show");

●

I would like to find the % of the area to the left of on the x axis when compared to the total % of the total area under the graph.

I hope that makes sense as a request.

Thanks in advance.

Alex

Answer 1

[dpb]

See cumtrapz