Plot with break in curve

%% I am trying to plot using the command plot(x,y,'DisplayName','E'), by using the data as shown below:

%% x y

0.0000 -963.0477

0.0043 -961.9818

0.0085 -960.8602

0.0128 -959.6834

0.0171 -958.4515

0.0214 -957.1649

0.0256 -955.8239

0.0299 -954.4289

0.0342 -952.9801

0.0385 -951.4780

0.0427 -949.9230

0.0000 -863.7275

0.0043 -862.6394

0.0085 -861.4965

0.0128 -860.2993

0.0171 -859.0485

0.0214 -857.7448

0.0256 -856.3888

0.0299 -854.9813

0.0342 -853.5229

0.0385 -852.0146

0.0427 -850.4570

0.0000 -478.7403

0.0043 -478.0232

0.0085 -477.2695

0.0128 -476.4793

0.0171 -475.6530

0.0214 -474.7909

0.0256 -473.8934

0.0299 -472.9608

0.0342 -471.9935

0.0385 -470.9920

0.0427 -469.9565

0.0000 142.4990

0.0043 141.8359

0.0085 141.1374

0.0128 140.4037

0.0171 139.6348

0.0214 138.8308

0.0256 137.9917

0.0299 137.1176

0.0342 136.2085

0.0385 135.2646

0.0427 134.2860

0.0000 178.0669

0.0043 178.4201

0.0085 178.7855

0.0128 179.1619

0.0171 179.5483

0.0214 179.9436

0.0256 180.3468

0.0299 180.7566

0.0342 181.1720

0.0385 181.5916

0.0427 182.0144

0.0000 460.9589

0.0043 459.2786

0.0085 457.5096

0.0128 455.6524

0.0171 453.7071

0.0214 451.6741

0.0256 449.5538

0.0299 447.3464

0.0342 445.0524

0.0385 442.6722

0.0427 440.2061

%% Here data for x sxcale reeat from 0 to 0.0427 six times, when I plot, then a line I laos found form 0.0427 to 0.0000, and five lines I found in %%plot, I do not want to plot between these points or I don;t want these five lines, I wants to break curve after 0.427. Along with this, I also %%want to add horizontal line at 0.0128 and 0.0342 on x-axis and vertical line at 453.7071 on y-axis.

[SHARAD KUMAR UPADHYAY]

It is working, also for long range of x-y data.

Answer 1

[Walter Roberson]

data = [%% x        y
    0.0000 -963.0477
    0.0043 -961.9818
    0.0085 -960.8602
    0.0128 -959.6834
    0.0171 -958.4515
    0.0214 -957.1649
    0.0256 -955.8239
    0.0299 -954.4289
    0.0342 -952.9801
    0.0385 -951.4780
    0.0427 -949.9230
    0.0000 -863.7275
    0.0043 -862.6394
    0.0085 -861.4965
    0.0128 -860.2993
    0.0171 -859.0485
    0.0214 -857.7448
    0.0256 -856.3888
    0.0299 -854.9813
    0.0342 -853.5229
    0.0385 -852.0146
    0.0427 -850.4570
    
    0.0000 -478.7403
    0.0043 -478.0232
    0.0085 -477.2695
    0.0128 -476.4793
    0.0171 -475.6530
    0.0214 -474.7909
    0.0256 -473.8934
    0.0299 -472.9608
    0.0342 -471.9935
    0.0385 -470.9920
    0.0427 -469.9565
    0.0000  142.4990
    0.0043  141.8359
    0.0085  141.1374
    0.0128  140.4037
    0.0171  139.6348
    0.0214  138.8308
    0.0256  137.9917
    0.0299  137.1176
    0.0342  136.2085
    0.0385  135.2646
    0.0427  134.2860
    
    0.0000  178.0669
    0.0043  178.4201
    0.0085  178.7855
    0.0128  179.1619
    0.0171  179.5483
    0.0214  179.9436
    0.0256  180.3468
    0.0299  180.7566
    0.0342  181.1720
    0.0385  181.5916
    0.0427  182.0144
    0.0000  460.9589
    0.0043  459.2786
    0.0085  457.5096
    0.0128  455.6524
    0.0171  453.7071
    0.0214  451.6741
    0.0256  449.5538
    0.0299  447.3464
    0.0342  445.0524
    0.0385  442.6722
    0.0427  440.2061];

x = reshape(data(:,1), 11, []);
y = reshape(data(:,2), 11, []);
x(12,:) = nan;
y(12,:) = nan;

plot(x(:), y(:));
xline([0.0128, 0.0342], 'k');
yline(453.7071, 'g');

[SHARAD KUMAR UPADHYAY]

It works. But little more suggestion I need as data range from 0.0000 to 1.7071 instead of 0.0000 to 0.0427. I am attaching the data file in .txt format where plot the data between coloumn 1 and 2 or 3 and 4. And put the horizontal and vertical (two or more) line automatically in plot, if possible.

[Walter Roberson]

The code I posted does not limit itself to 0.0427 -- that value is chosen automatically according to the data.

You could specifically xlim([0 1.7071] but that would make about 39 out of 40 parts of the plot blank.

Your file does not have 4 columns.

filename = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/1078840/CO-ph-d.txt';
data = readmatrix(filename);

x = reshape(data(:,1), 11, []);
y = reshape(data(:,2), 11, []);
x(12,:) = nan;
y(12,:) = nan;
plot(x(:), y(:));
xline([0.0128, 0.0342], 'k');
yline(453.7071, 'g');

[SHARAD KUMAR UPADHYAY]

%% 0.0000 repeats after 401 line. I have tried to do this as

A=importdata("./QE-PH/CO-ph-d.txt"); %% readmatrix also work as well as importdata

x = reshape(A(:,1), 401, []);

y = reshape(A(:,2), 401, []);

x(402,:) = nan;

y(402,:) = nan;

plot(x(:), y(:));

% xline([0.0128, 0.0342], 'k');

% yline(453.7071, 'r');

%% I found the error as

Error using reshape

Product of known dimensions, 401, not divisible into total number of elements, 66.

Error in Toplot (line 8)

x = reshape(A(:,1), 401, []);

[Walter Roberson]

For that data file, 0.0000 repeats every 11, not every 401. The entire file only has 66 data lines.

The following code tries to automatically detect the length before repetition.

filename = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/1079015/CO-ph-d.txt';
data = readmatrix(filename);
col1 = data(:,1);
repeatlength = find(col1(2:end) == col1(1), 1);

x = reshape(data(:,1), repeatlength, []);
y = reshape(data(:,2), repeatlength, []);
x(end+1,:) = nan;
y(end+1,:) = nan;
plot(x(:), y(:));

[SHARAD KUMAR UPADHYAY]

Last answer is also working, and this answer is more useful.

Answer 2

[Chunru]

xy=[0.0000 -963.0477
    0.0043 -961.9818
    0.0085 -960.8602
    0.0128 -959.6834
    0.0171 -958.4515
    0.0214 -957.1649
    0.0256 -955.8239
    0.0299 -954.4289
    0.0342 -952.9801
    0.0385 -951.4780
    0.0427 -949.9230
    0.0000 -863.7275
    0.0043 -862.6394
    0.0085 -861.4965
    0.0128 -860.2993
    0.0171 -859.0485
    0.0214 -857.7448
    0.0256 -856.3888
    0.0299 -854.9813
    0.0342 -853.5229
    0.0385 -852.0146
    0.0427 -850.4570
    
    0.0000 -478.7403
    0.0043 -478.0232
    0.0085 -477.2695
    0.0128 -476.4793
    0.0171 -475.6530
    0.0214 -474.7909
    0.0256 -473.8934
    0.0299 -472.9608
    0.0342 -471.9935
    0.0385 -470.9920
    0.0427 -469.9565
    0.0000  142.4990
    0.0043  141.8359
    0.0085  141.1374
    0.0128  140.4037
    0.0171  139.6348
    0.0214  138.8308
    0.0256  137.9917
    0.0299  137.1176
    0.0342  136.2085
    0.0385  135.2646
    0.0427  134.2860
    
    0.0000  178.0669
    0.0043  178.4201
    0.0085  178.7855
    0.0128  179.1619
    0.0171  179.5483
    0.0214  179.9436
    0.0256  180.3468
    0.0299  180.7566
    0.0342  181.1720
    0.0385  181.5916
    0.0427  182.0144
    0.0000  460.9589
    0.0043  459.2786
    0.0085  457.5096
    0.0128  455.6524
    0.0171  453.7071
    0.0214  451.6741
    0.0256  449.5538
    0.0299  447.3464
    0.0342  445.0524
    0.0385  442.6722
    0.0427  440.2061];
whos

  Name         Size            Bytes  Class     Attributes

  cmdout       1x33               66  char                
  xy          66x2              1056  double              

n = 11; 
figure; hold on
for i=0:5
    plot(xy(i*n+(1:n), 1), xy(i*n+(1:n), 2))
end