Cody

# Problem 42854. Crunch that matrix!

Solution 910820

Submitted on 17 Jun 2016
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### Test Suite

Test Status Code Input and Output
1   Fail
a=reshape(1:36,6,[]); b=[sum(a(:,1:3),2) sum(a(:,4:6),2)]; m=matrix_crunch(a); assert(max(max(abs(m-b)))<1e-10)

Error using matrix_crunch (line 2) Undefined function or variable 'a'.

2   Fail
a=magic(9)-30; b=[sum(a(:,1:3),2) sum(a(:,4:6),2) sum(a(:,7:9),2)]; m=matrix_crunch(a); assert(max(max(abs(m-b)))<1e-10)

Error using matrix_crunch (line 2) Undefined function or variable 'a'.

3   Fail
a=rand(12); b=[sum(a(:,1:3),2) sum(a(:,4:6),2) sum(a(:,7:9),2) sum(a(:,10:12),2)]; m=matrix_crunch(a); assert(max(max(abs(m-b)))<1e-10)

Error using matrix_crunch (line 2) Undefined function or variable 'a'.

4   Fail
a=ones(18); b=3*ones(18,6); m=matrix_crunch(a); assert(max(max(abs(m-b)))<1e-10)

Error using matrix_crunch (line 2) Undefined function or variable 'a'.

5   Fail
a=magic(15)+j.*flipud(magic(15)); a=a(1:10,:)-rand(10,15); b=[sum(a(:,1:3),2) sum(a(:,4:6),2) sum(a(:,7:9),2) sum(a(:,10:12),2) sum(a(:,13:15),2)]; m=matrix_crunch(a); assert(max(max(abs(m-b)))<1e-10)

Error using matrix_crunch (line 2) Undefined function or variable 'a'.