Matrix arithmeticsΒΆ
The following description of matrix arithmetics applies to all storage classes. The following matrix operators have been implemented:
C++
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | GMatrix A(10,10); // A 10 x 10 matrix
GMatrix B(10,10); // Another 10 x 10 matrix
GMatrix C; // Result matrix
GVector v(10); // Vector with 10 elements
double s = 2.0; // Floating point value
C = A + B; // Matrix addition
C = A - B; // Matrix subtraction
C = A * B; // Matrix multiplication
C = A * v; // Vector multiplication
C = A * s; // Right-handed scalar multiplication
C = s * A; // Left-handed scalar Matrix multiplication (only C++)
C = A / s; // Scalar division
C = -A; // Negation
A += B; // Unary matrix addition
A -= B; // Unary matrix subtraction
A *= B; // Unary matrix multiplications
A *= s; // Unary matrix scalar multiplication
A /= s; // Unary matrix scalar division
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Python
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 | A = gammalib.GMatrix(10,10) # A 10 x 10 matrix
B = gammalib.GMatrix(10,10) # Another 10 x 10 matrix
v = gammalib.GVector(10) # Vector with 10 elements
s = 2.0 # Floating point value
C = A + B # Matrix addition
C = A - B # Matrix subtraction
C = A * B # Matrix multiplication
C = A * v # Vector multiplication
C = A * s # Scalar multiplication
C = A / s # Scalar division
C = -A # Negation
A += B # Unary matrix addition
A -= B # Unary matrix subtraction
A *= B # Unary matrix multiplications
A *= s # Unary matrix scalar multiplication
A /= s # Unary matrix scalar division
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You can use the comparison operators
C++
1 2 | int equal = (A == B); // True if all elements equal
int unequal = (A != B); // True if at least one elements unequal
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Python
1 2 | equal = (A == B) # True if all elements equal
unequal = (A != B) # True if at least one elements unequal
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In addition to the operators, you can apply the following mathematical functions to a matrix:
C++
1 2 3 4 5 6 7 | C = A.abs(); // Matrix with absolute values of all matrix elements
C = A.transpose(); // Transpose matrix
C = A.invert(); // Invert matrix
v = A.solve(v); // Solve matrix equation x = M x v
s = A.min(); // Minimum element of matrix
s = A.max(); // Maximum element of matrix
s = A.sum(); // Sum of matrix elements
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Python
1 2 3 4 5 6 7 | C = A.abs() # Matrix with absolute values of all matrix elements
C = A.transpose() # Transpose matrix
C = A.invert() # Invert matrix
v = A.solve(v) # Solve matrix equation x = M x v
s = A.min() # Minimum element of matrix
s = A.max() # Maximum element of matrix
s = A.sum() # Sum of matrix elements
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Warning
The invert() and solve() methods are so far only implemented for
sparse matrices.