• Vino (8/8) Mar 30 2020 Hi All,
• jmh530 (20/28) Mar 30 2020 This should be in the Learn forum.
• jmh530 (12/14) Mar 30 2020 The relevant function signature is
• 9il (3/11) Mar 30 2020 static immutable y = [1.0, 3, 2, 5, 7, 8, 8, 9, 10, 12];

Vino <akashvino79 gmail.com> writes:

Hi All,

   Can anyone  guide me what is the problem  with below code as it 
throws  error.

import std.stdio, mir.math.common: approxEqual;
static immutable x = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
static immutable y = [1, 3, 2, 5, 7, 8, 8, 9, 10, 12];
auto params = x.simpleLinearRegression(y);
writeln(params);

jmh530 <john.michael.hall gmail.com> writes:

On Monday, 30 March 2020 at 17:21:57 UTC, Vino wrote:
 Hi All,

   Can anyone  guide me what is the problem  with below code as 
 it throws  error.

 import std.stdio, mir.math.common: approxEqual;
 static immutable x = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
 static immutable y = [1, 3, 2, 5, 7, 8, 8, 9, 10, 12];
 auto params = x.simpleLinearRegression(y);
 writeln(params);

This should be in the Learn forum.

As far as I can tell, the problem is that x and y are both type 
immutable(int[]), which it cannot handle. I tried just turning 
them into slices, but that wasn't sufficient, I had to ensure 
they were double as well (float would also work). Note that the 
example in the document uses a y variable that is a floating 
point type.

/+dub.sdl:
dependency "mir-algorithm" version="~>3.7.25"
+/
import std.stdio : writeln;
import mir.math.stat : simpleLinearRegression;
import mir.ndslice : sliced;

void main() {
     auto x = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9].sliced!double;
     auto y = [1, 3, 2, 5, 7, 8, 8, 9, 10, 12].sliced!double;
     auto params = x.simpleLinearRegression(y);
     writeln(params);
}

jmh530 <john.michael.hall gmail.com> writes:

On Monday, 30 March 2020 at 17:47:19 UTC, jmh530 wrote:
 
 [snip]

The relevant function signature is

 safe sumType!YRange[2] simpleLinearRegression(XRange, 
YRange)(XRange x, YRange y)
if (isInputRange!XRange && isInputRange!YRange && 
!(isArray!XRange && isArray!YRange) && 
isFloatingPoint!(sumType!YRange));

and when you pass an int[] for y, then it determines that int is 
not a floating point and you get an error about not matching the 
signature, nothing about why you're not matching it.

A good example of where Atila's concepts library would be 
helpful...

9il <ilyayaroshenko gmail.com> writes:

On Monday, 30 March 2020 at 17:21:57 UTC, Vino wrote:
 Hi All,

   Can anyone  guide me what is the problem  with below code as 
 it throws  error.

 import std.stdio, mir.math.common: approxEqual;
 static immutable x = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];
 static immutable y = [1, 3, 2, 5, 7, 8, 8, 9, 10, 12];
 auto params = x.simpleLinearRegression(y);
 writeln(params);

static immutable y = [1.0, 3, 2, 5, 7, 8, 8, 9, 10, 12];

`.0` will change the sum type of y to double.