MATLAB Answers

How to get NaN when txt file is not exist

1 view (last 30 days)
BENJAMIN BUCHDA
BENJAMIN BUCHDA on 23 Feb 2021
Commented: Walter Roberson on 18 Mar 2021
This is a working function that gets the min, average, max of numbers with a specific row thershold however if i wanted to get an 'NaN' if the txt file or specfic column does not exist, how would I do that?
function res = columnStatistics(fPath, cat, cName)
fConn = fopen(fPath, 'r');
firstLine = fgetl(fConn);
new = [];
while ~feof(fConn)
cLine = fgetl(fConn);
Y = strsplit(firstLine, ',');
X = ismember(Y, cName);
V = find(X);
parts = strsplit(cLine, ',');
O = str2double(parts(V));
tru = strcmp(cat, parts{1});
if (tru)
new(end+1) = O;
else
res = [NaN];
end
end
fclose(fConn);
minData = min(new);
aveData = mean(new);
maxData = max(new);
final = [minData, aveData, maxData];
res = final;
end
  2 Comments
Walter Roberson
Walter Roberson on 18 Mar 2021
You posted a question about labeling bars in alphabetic order, but deleted the question before my response made it up.
I post it here as the answer is not obvious.
====
Generalizing it to alphabetic when there was more than 26 possibilities was a bit tricky.
You should consider using categorical data for your x axis.
yData = (randi(9, 1, 30));
W = max(yData);
U = W + 5;
myFig = gcf;
myAx = axes(myFig);
myPlot = bar(myAx, yData);
myPlot.FaceColor = 'flat';
myAx.XTick = 1:length(yData);
myAx.YLim = [0 U];
myAx.Title.String = 'Data Visualization';
myAx.YLabel.String = 'Value';
myAx.XLabel.String = 'Category';
for i = 1:length(yData)
temp = dec2base(i-1,26);
temp(1:end-1) = temp(1:end-1) - 1;
myLab = blanks(length(temp));
mask = temp <= '9';
myLab(mask) = char(temp(mask) - '0' + 'A');
myLab(~mask) = char(temp(~mask) + 10);
myAx.XAxis.TickLabels{i} = myLab;
end

Sign in to comment.

Answers (1)

Shashank Gupta
Shashank Gupta on 25 Feb 2021
Hey Benjamin,
Check out textscan function, it is useful in the same scenerio as you are interested in. This will help you fill up empty places in the data.
I hope this helps.
Cheers

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by