Main program written in C++
Reference : Practical Makefiles, by example
void operations();
int main(int argc, const char **argv) {
operations();
return 0;
}Reference : Practical Makefiles, by example
void operations();
int main(int argc, const char **argv) {
operations();
return 0;
}#include <iostream>
#include <armadillo>
void operations() {
// Initialize the random generator
arma::arma_rng::set_seed_random();
// Create a 4x4 random matrix and print it on the screen
arma::Mat<double> A = arma::randu(4,4);
std::cout << "A:\n" << A << "\n";
// Multiply A with his transpose:
std::cout << "A * A.t() =\n";
std::cout << A * A.t() << "\n";
// Access/Modify rows and columns from the array:
A.row(0) = A.row(1) + A.row(3);
A.col(3).zeros();
std::cout << "add rows 1 and 3, store result in row 0, also fill 4th column with zeros:\n";
std::cout << "A:\n" << A << "\n";
// Create a new diagonal matrix using the main diagonal of A:
arma::Mat<double>B = arma::diagmat(A);
std::cout << "B:\n" << B << "\n";
// Save matrices A and B:
A.save("A_mat.txt", arma::arma_ascii);
B.save("B_mat.txt", arma::arma_ascii);
}c++ -c files/obj_armadillo.cpp -I/opt/local/include # create the file obj_armadillo.o
c++ -o exe_armadillo files/main.cpp obj_armadillo.o -L/opt/local/lib -larmadillo # create the executable exe_armadillo.o-I option flag to set headers file directory (.h) needed to build every object files (CXXFLAGS).-L option flag to set library directory (.a) needed only to build executable (LDFLAGS)./exe_armadillo
rm ./exe_armadillo *.o## A:
## 0.5037 0.8103 0.3284 0.0446
## 0.3764 0.3620 0.1811 0.9196
## 0.4333 0.9092 0.7558 0.9676
## 0.5202 0.1974 0.2192 0.6029
##
## A * A.t() =
## 1.0201 0.5834 1.2462 0.5209
## 0.5834 1.1513 1.5190 0.8615
## 1.2462 1.5190 2.5218 1.1540
## 0.5209 0.8615 1.1540 0.7212
##
## add rows 1 and 3, store result in row 0, also fill 4th column with zeros:
## A:
## 0.8966 0.5595 0.4003 0
## 0.3764 0.3620 0.1811 0
## 0.4333 0.9092 0.7558 0
## 0.5202 0.1974 0.2192 0
##
## B:
## 0.8966 0 0 0
## 0 0.3620 0 0
## 0 0 0.7558 0
## 0 0 0 0
default: exe_armadillo
obj_armadillo.o: files/obj_armadillo.cpp
c++ -o $@ -c $^ -I/opt/local/include
exe_armadillo: files/main.cpp obj_armadillo.o
c++ -o $@ $^ -L/opt/local/lib -larmadillo
clean:
rm *.txt *.o exe_armadillomake -f files/Makefile1
./exe_armadillo
make -f files/Makefile1 clean## c++ -o obj_armadillo.o -c files/obj_armadillo.cpp -I/opt/local/include
## c++ -o exe_armadillo files/main.cpp obj_armadillo.o -L/opt/local/lib -larmadillo
## A:
## 0.1992 0.0072 0.3641 0.7114
## 0.0285 0.4529 0.9766 0.2345
## 0.1830 0.2280 0.8833 0.1920
## 0.2773 0.2637 0.3530 0.8260
##
## A * A.t() =
## 0.6784 0.5314 0.4963 0.7733
## 0.5314 1.2147 1.0161 0.6658
## 0.4963 1.0161 0.9025 0.5813
## 0.7733 0.6658 0.5813 0.9533
##
## add rows 1 and 3, store result in row 0, also fill 4th column with zeros:
## A:
## 0.3057 0.7166 1.3296 0
## 0.0285 0.4529 0.9766 0
## 0.1830 0.2280 0.8833 0
## 0.2773 0.2637 0.3530 0
##
## B:
## 0.3057 0 0 0
## 0 0.4529 0 0
## 0 0 0.8833 0
## 0 0 0 0
##
## rm -f *.txt *.o exe_armadillo
default: exe_armadillo # default target
CXX := c++ # := means "change CXX only if it is undefined"
ARMADILLO_INCDIR = /opt/local/include
ARMADILLO_LIBDIR = /opt/local/lib
ARMADILLO_INC_FLAGS = -I${ARMADILLO_INCDIR}
ARMADILLO_LIB_FLAGS = -L${ARMADILLO_LIBDIR} -larmadillo
obj_armadillo.o: files/obj_armadillo.cpp
${CXX} -c -o $@ $^ ${ARMADILLO_INC_FLAGS} # $@ : target $^: dependencies
exe_armadillo: files/main.cpp obj_armadillo.o
${CXX} -o $@ $^ ${ARMADILLO_LIB_FLAGS}
clean:
rm *.txt *.o exe_armadillomake -f files/Makefile2
./exe_armadillo
make -f files/Makefile2 clean## c++ -c -o obj_armadillo.o files/obj_armadillo.cpp -I/opt/local/include # obj_armadillo.o : target files/obj_armadillo.cpp: dependencies
## c++ -o exe_armadillo files/main.cpp obj_armadillo.o -L/opt/local/lib -larmadillo
## A:
## 0.1632 0.0166 0.9071 0.9214
## 0.9668 0.4183 0.7988 0.8361
## 0.1602 0.1298 0.3475 0.1719
## 0.8506 0.2413 0.9478 0.8199
##
## A * A.t() =
## 1.6988 1.6597 0.5019 1.7581
## 1.6597 2.4468 0.6305 2.3659
## 0.5019 0.6305 0.1928 0.6379
## 1.7581 2.3659 0.6379 2.3523
##
## add rows 1 and 3, store result in row 0, also fill 4th column with zeros:
## A:
## 1.8173 0.6597 1.7466 0
## 0.9668 0.4183 0.7988 0
## 0.1602 0.1298 0.3475 0
## 0.8506 0.2413 0.9478 0
##
## B:
## 1.8173 0 0 0
## 0 0.4183 0 0
## 0 0 0.3475 0
## 0 0 0 0
##
## rm *.txt *.o exe_armadillo
default: exe_armadillo
CXX := c++
ARMADILLO_INCDIR = /opt/local/include
ARMADILLO_LIBDIR = /opt/local/lib
ARMADILLO_INC_FLAGS = -I${ARMADILLO_INCDIR}
ARMADILLO_LIB_FLAGS = -L${ARMADILLO_LIBDIR} -larmadillo
CXXFLAGS += ${ARMADILLO_INC_FLAGS}
LDFLAGS += ${ARMADILLO_LIB_FLAGS}
SRCS = $(wildcard *.cpp) # List all cpp files
OBJS = $(SRCS:.cpp=.o) # List all matching object files
.cpp.o: # $< the source file .cpp $@ the target .o
$(CXX) $(CXXFLAGS) -c $< -o $@
exe_armadillo: $(OBJS)
${CXX} -o $@ $^ $(CXXFLAGS) ${LDFLAGS}
clean:
rm *.txt *.o exe_armadillomake -f Makefile3
./exe_armadillo
make -f Makefile3 clean