How can I organize data into monthly means/averages across all years? And then plot it in a bar graph?

12 次查看（过去 30 天）
Macy
Macy 2023-4-26
回答： Sugandhi 2023-4-26
Ran in:
Hello, I would like to make a barplot of average monthly number of students, in other words the mean of the total students across all school years. So the x-axis would read August, September, October, etc. and the y axis would be the average number of students in that month across all years.
I am not sure where to start on this, below is just some code for students per year, not related to what I am trying to find.
Table = readtable("Student_data.xlsx"); % Read in data
%Part 3: Assign school year (SY) to each daily observation
SY = zeros(size(Table.month));
for i = 1:height(Table)
if Table.month(i)>=8 % months "greater" than or equal to August (month 8) are in the following schoolyear, so add 1 yr
SY(i) = Table.year(i) + 1;
else
SY(i) = Table.year(i); % months "lesser" than August are in the regular year
end
end
Table.schoolyear = SY(:); % add "schoolyear" as a column in Table
%For each school year, sum up the total students just for that year.
g = findgroups(Table.schoolyear); % "group" the unique school years
students = splitapply(@sum, Table.students, g);% sum the total students of each school year "group"
year = splitapply(@mean, Table.schoolyear, g);
%Make a Barplot for annual total students
bar(year,students);
ylabel("Students");
xlabel("School Year");
title("Annual Student Totals");
% Now make a barplot of monthly mean students
% I am stuck here
  1 个评论
Antoni Garcia-Herreros
Antoni Garcia-Herreros 2023-4-26
Ran in:
Hello Macy,
You could try something like this:
Table = readtable("Student_data.xlsx");
Mat=table2array(Table);
Months=zeros(12,1);
for i=1:12
imonth=Mat(Mat(:,1)==i,4);
Months(i)=sum(imonth);
end
MonthLabel={'Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'};
bar(Months);
ylabel("Students");
xlabel("Month");
title("Monthly Student Totals");
set(gca,'xticklabel',MonthLabel);
Error using readtable
Unable to find or open 'Student_data.xlsx'. Check the path and filename or file permissions.

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Sugandhi
Sugandhi 2023-4-26
Hi,
I understand that you would like to make a barplot of average monthly number of students.
You can solve your problem something like this:
Table = readtable("Student_data.xlsx"); % Read in data
monthNames= {'Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'};
SY = zeros(size(Table.month));
for i = 1:height(Table)
if Table.month(i)>=8 % months "greater" than or equal to August (month 8) are in the following schoolyear, so add 1 yr
SY(i) = Table.year(i) + 1;
else
SY(i) = Table.year(i); % months "lesser" than August are in the regular year
end
end
Table.schoolyear = SY(:); % add "schoolyear" as a column in Table
%For each month, sum up the total students for all year and divide by total number of years.
g = findgroups(Table.schoolyear);% "group" the unique school years
year = splitapply(@mean, Table.schoolyear, g); % get unique years
TotalYears= size(year);
TotalYears=TotalYears(1,1); %get total number of years
g1 = findgroups(Table.month); % "group" the unique months
totalStudents = splitapply(@sum, Table.students, g1); % sum the total students of each school month "group"
months=splitapply(@mean, Table.month, g1); % get unique month
avgStudents= totalStudents/TotalYears(1); % get average monthly number of students.
%Make a Barplot for average monthly number of students
bar(months,avgStudents);
ylabel("Students");
xlabel("Month");
title("Average monthly number of students");
set(gca,'xticklabel',monthNames);

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Dates and Time 的更多信息

标签

产品


版本

R2023a

Community Treasure Hunt

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

Start Hunting!

Translated by