plotting .mat file......

83 次查看（过去 30 天）

Murtaza Ali Khan 2017-4-26

2
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/337398-plotting-mat-file

评论： Nawsheen Tarannum Promy 2020-10-22

Hi, I want to plot from spectrum.mat file but it giving me following error. Error using plot Invalid first data argument. Error in data (line 5) plot('spectrum.mat')

But when I exactly load this file then it loading and at right in 'workspace box' giving "spec 401x2 double" values.

Could anyone please let me know that why I can't plot this "spectrum.mat" file, kindly if someone show me the procedure for plotting .mat files. By the way in this spectrum.mat file there are two columns (e.g x-axis Frequency and y-axis Scale) and 401 rows.

Thanks

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Jan 2017-4-26

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/337398-plotting-mat-file#answer_264590

在 MATLAB Online 中打开

"plot('spectrum.mat')"?! This tries to plot the char vector 'spectrum.mat'.

You cannot plot a file. You have to load the data at first:

Data = load('spectrum.mat');

Now you can plot the data, perhaps by:

plot(Data.spec)

plot(Data.spec(:,1), Data.spec(:,2))

7 个评论
显示 5更早的评论隐藏 5更早的评论

Walter Roberson 2020-10-5

Yes, the x2 indicates two columns. This is standard output format for "whos", the dimension sizes separated by 'x'

You do appear to have 200 columns.

You can use that syntax, provided that the name of the saved variable is spec and you assign the result of load() to the variable named Data

However, I suspect that would be the wrong thing to do. I suspect that you have either 4853 stress sites sampled at 200 times, or else 200 stress sites sampled at 4853 times. I suspect you should use something more like a waterfall plot.