Problem 970. Piecewise linear interpolation

Created by James

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1467 Solutions
479 Solvers

Last Solution submitted on Mar 14, 2023

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Problem Comments

2 Comments

2 Comments

Elmar Zander on 23 Mar 2017

It seems someone messed up the test code: the defintion of x for the first test is now in the comment line and its impossible now to solve the problem (except cheating...)

Xiaoyi Chin on 18 Sep 2017

I think there is something wrong with the test.

Solution Comments

Solution 1210322

5 Comments

5 Comments

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Informaton on 12 Jun 2017

This is showing some strange behavior. If you use the second solution for y, the hard coded answer, it fails the first test case and also shows differing input values for the original x and y. However, if you use the first solution for y (taken from Alfonso's solution), then the correct input values for x and y are shown. I don't understand how the input values for the test suite do not match (you can see the values displayed in the answer.

James on 10 Apr 2018

Just noticed the issues that some people were having with this problem. I added a "%%" at the start of the test suite, which has helped in the past. Rescoring the two solutions that you have commented on fixed your problems. Your hard coded answer now works, and all three of the test cases show up in your test suite.

David Verrelli on 10 May 2018

Hello, James. Any chance you could check the somewhat similar Cody bug I seem to encounter with Problem 753? I am puzzled as to why it only affects some Players. Thanks, DIV.

David Verrelli on 25 May 2018

Thanks for the suggestion, James. I didn't get a response from them, but the fatal bug in the Test Suite of Problem 753 has somehow morphed into a non-fatal bug anyway. —DIV

David Verrelli on 1 Jun 2018

...Or not. Anyway, I think I've figured out the way Test Suites are parsed in Cody: "%%" defines the start of a new test case, and omission of "%%" for the first lines of code means they become _shared variables_! Sorry for going off-topic (w.r.t. piecewise linear interpolation), but I couldn't see this documented anywhere. It is actually quite handy, as per the Test Suite in Problem 44655. —DIV

Solution 1209901

1 Comment

1 Comment

Informaton on 11 Jun 2017

Too bad the test cases don't work anymore :(
I get the same input for x and y each time

x = 1 1 3 0 1 1
y = 5 3

Solution 1047978

1 Comment

1 Comment

Jan Orwat on 8 Nov 2016

This solution shows a little bit different approach to the problem. It leads to nice, short code.

Solution 195302

2 Comments

2 Comments

Alfonso Nieto-Castanon on 22 Jan 2013

There are some rounding issues with the test suite. assert(isequal(a,b)) where a and b are doubles can be problematic. I would suggest using assert(all(all(abs(a-b)<1e-10))) or something similar instead

James on 23 Jan 2013

I picked out the numbers in the test cases to hopefully avoid doing that. Looks like your solution (which is quite impressive, btw) runs into the issues I was hoping to avoid.

I'll change the assert condition in a bit.

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