Difference between revisions of "C++:3D Exercises"

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(Normalise a vector)
 
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{{3D Exercise}}
 
==Dot Product==
 
==Dot Product==
 
<question>
 
<question>
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}
 
}
  
float *crossproduct(float a[3], float b[3]){
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void crossproduct(float r[3],float a[3],float b[3]){
  float *r = new float[3];
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   // Your code goes here, change the result - r
   // Your code goes here
 
  return r;
 
 
}
 
}
  
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   float A[]={1,0,1};
 
   float A[]={1,0,1};
 
   float B[]={1,1,2};
 
   float B[]={1,1,2};
   float *C = crossproduct(A,B);
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   float C[3];
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  crossproduct(C,A,B);
 
   cout << C[0]<<" "<<C[1]<<" "<<C[2]<< endl;
 
   cout << C[0]<<" "<<C[1]<<" "<<C[2]<< endl;
 
   return 0;
 
   return 0;
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using namespace std;
 
using namespace std;
  
float length(float a[3]){
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void normalise(float r[3],float a[3]){
   float r=0; // Your code goes here
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   //Your code here. set r to normalise a
  return r;
 
 
}
 
}
  
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   float A[]={1,0,1};
 
   float A[]={1,0,1};
 
   float B[]={1,1,2};
 
   float B[]={1,1,2};
   cout << length(A)<< endl;
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  float C[3];
   cout << length(B)<< endl;
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  normalise(C,A);
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   cout << C[0]<<" "<<C[1]<<" "<<C[2]<< endl;
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  normalise(C,B);
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   cout << C[0]<<" "<<C[1]<<" "<<C[2]<< endl;
 
   return 0;
 
   return 0;
 
}
 
}
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<answer><![CDATA[
 
<answer><![CDATA[
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#include <math.h>
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#include <iostream>
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using namespace std;
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 +
float length(float a[3]){
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  float r=sqrt(a[0]*a[0]+a[1]*a[1]+a[2]*a[2]);
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  return r;
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}
 +
 +
void scalarproduct(float r[3],float x,float a[3]){
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  for (int i=0;i<3;i++)
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    r[i] = x*a[i];
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}
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int main(int argc, char **argv)
 +
{
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  float A[]={1,0,1};
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  float B[]={1,1,2};
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  float C[3];
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  scalarproduct(C,1.0/length(A),A);
 +
  cout << C[0]<<" "<<C[1]<<" "<<C[2]<< endl;
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  scalarproduct(C,1.0/length(B),B);
 +
  cout << C[0]<<" "<<C[1]<<" "<<C[2]<< endl;
 +
  return 0;
 +
}
 
]]></answer>
 
]]></answer>
 
</question>
 
</question>
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]]></answer>
 
]]></answer>
 
</question>
 
</question>
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{{3D Exercise}}

Latest revision as of 12:12, 25 November 2011

Dot Product

Calculate the dot product of two vectors. Fill in the details in the function dotproduct

Wikipedia includes a good article on dot products. http://en.wikipedia.org/wiki/Dot_product#Definition



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Cross Product

Calculate the cross product of two vectors. Fill in the details in the function crossproduct

Wikipedia includes a good article on cross products. http://en.wikipedia.org/wiki/Cross_product#Coordinate_notation



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Vector Length

Calculate the magnitude of a vector. Fill in the details in the function length



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Normalise a vector

Normalise the given vector. The direction should be the same, the length should be 1.



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Normal to a plane

Find the unit normal to the plane that contains the three points given.



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