cell2mat has a very specific condition

2 ビュー (過去 30 日間)
daniel slama
daniel slama 2022 年 6 月 20 日
コメント済み: dpb 2022 年 6 月 20 日
hey all! so i've been playing with cells and structures etc.
i have a structure 'students' with fields:name,id,grades.
in grades i have a nx1 cell array where n is the number of grades per students. the grades are in string and not numbers.
i wanted to calculate every student's avarage. i used a for loop and cell2mat and it gave me an nx2 matrix of char objects.
the problem is the last students, one of his grades is 100 which is 3 letters instead of 2 and because of that cell2mat has no idea how to compensate for it.
i know i could have made things easier for myself if i made a more normal structure in the first place but i'm too far in the excercise now lol.
any idea how to work with this?
  2 件のコメント
daniel slama
daniel slama 2022 年 6 月 20 日
of course, my bad.
this is my attempt to calculate every student's avarage with notes of what i tried to to every line.
[a b]=size(students)
for i = [1:1:b]
charmat=cell2mat(students(i).grades) %creates the nx2 matrix and gets stuck with the last student
[c d]=size(charmat)
for x = [1:1:c]
nummat=[nummat ; temp] %makes a number matrix out of the char matrix



dpb 2022 年 6 月 20 日
Indeed, you made dereferencing the data about as hard as could by putting it into cell array -- a struct could/can hold an ordinary array; it shouldn't be too hard to change the code to make the grades arrays numeric to start with...but one way to your objective here is\
>> arrayfun(@(i)mean(str2double(students(i).grades)),1:numel(students),'UniformOutput',true)
ans =
84.0000 98.5000 86.1667 57.3333 87.2500
  2 件のコメント
dpb 2022 年 6 月 20 日
Will become familiar idiom (along with the companion functions for cell arrays and sructure fields) with time...


その他の回答 (0 件)


Help Center および File ExchangeLoops and Conditional Statements についてさらに検索




Community Treasure Hunt

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

Start Hunting!

Translated by