diff --git a/.travis.yml b/.travis.yml
index 46f20e5..4e40507 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,11 @@
 language: c
-compiler: clang
+compiler: g++-4.8
 sudo: required
+dist: trusty
+
+install:
+  - sudo apt-get update -qq
+  - sudo apt-get install gcc-4.8 -y -qq
 
 script:
   - make all
diff --git a/Makefile b/Makefile
index 545eb15..e5be43e 100644
--- a/Makefile
+++ b/Makefile
@@ -1,25 +1,73 @@
 # Compiler flags
-CFLAGS=-I ./include -std=c++11 -Wall
-CFLAGS_LIB=-I ./include -std=c++11 -c
+CFLAGS=-I./include -std=gnu++11 -Wall
+CFLAGS_LIB=-I./include -std=gnu++11 -c
+CFLAGS_TEST=test/tmath_test.cpp build/libtmath.a
 
-all: lib
+all: lib test
+	@echo Done.
 
-lib: tmath.o
-	mkdir -p build
-	echo "Packaging library ..."
+lib: build_folder tmath.o
 	ar rcs build/libtmath.a build/tmath.o
 
-test: lib
-	echo "Running tests ..."
+test: test_sine test_cosine test_tangent test_cosecant test_cotangent test_secant test_rad_deg test_abs test_factorial test_roots test_power test_exp_log
+	@echo all tests passed
 
-examples: lib
-	echo "Building examples ..."
+build_folder:
+	@mkdir -p build
 
-tmath.o:
-	echo "Building source files ..."
-	mkdir -p build
+test_folder:
+	@mkdir -p build/test
+
+test_sine: test_folder
+	$(CC) $(CFLAGS) test/sine/test.cpp -o build/test/sine $(CFLAGS_TEST)
+	@build/test/sine
+
+test_cosine: test_folder
+	$(CC) $(CFLAGS) test/cosine/test.cpp -o build/test/cosine $(CFLAGS_TEST)
+	@build/test/cosine
+
+test_tangent: test_folder
+	$(CC) $(CFLAGS) test/tangent/test.cpp -o build/test/tangent $(CFLAGS_TEST)
+	@build/test/tangent
+
+test_cosecant: test_folder
+	$(CC) $(CFLAGS) test/cosecant/test.cpp -o build/test/cosecant $(CFLAGS_TEST)
+	@build/test/cosecant
+
+test_cotangent: test_folder
+	$(CC) $(CFLAGS) test/cotangent/test.cpp -o build/test/cotangent $(CFLAGS_TEST)
+	@build/test/cotangent
+
+test_secant: test_folder
+	$(CC) $(CFLAGS) test/secant/test.cpp -o build/test/secant $(CFLAGS_TEST)
+	@build/test/secant
+
+test_rad_deg: test_folder
+	$(CC) $(CFLAGS) test/rad-deg/test.cpp -o build/test/rad-deg $(CFLAGS_TEST)
+	@build/test/rad-deg
+
+test_abs: test_folder
+	$(CC) $(CFLAGS) test/abs/test.cpp -o build/test/abs $(CFLAGS_TEST)
+	@build/test/abs
+
+test_factorial: test_folder
+	$(CC) $(CFLAGS) test/factorial/test.cpp -o build/test/factorial $(CFLAGS_TEST)
+	@build/test/factorial
+
+test_roots: test_folder
+	$(CC) $(CFLAGS) test/roots/test.cpp -o build/test/roots $(CFLAGS_TEST)
+	@build/test/roots
+
+test_power: test_folder
+	$(CC) $(CFLAGS) test/power/test.cpp -o build/test/power $(CFLAGS_TEST)
+	@build/test/power
+
+test_exp_log: test_folder
+	$(CC) $(CFLAGS) test/exp-log/test.cpp -o build/test/exp-log $(CFLAGS_TEST)
+	@build/test/exp-log
+
+tmath.o: build_folder
 	$(CC) $(CFLAGS_LIB) src/tmath.cpp -o build/tmath.o
 
-clean:
-	echo "Cleaning up ..."
+clean: build_folder
 	rm build -f -r
diff --git a/examples/arcsec_demo.cpp b/examples/arcsec_demo.cpp
deleted file mode 100644
index 86c2343..0000000
--- a/examples/arcsec_demo.cpp
+++ /dev/null
@@ -1,10 +0,0 @@
-#include <stdio.h>
-#include "tmath.h"
-
-/*
-Demonstration of the TaylorMath (TMath) math function collection.
-*/
-int main(void) {
-	printf("%.128f \n", TMath::arcsec(2));
-	return 0;
-}
diff --git a/include/tmath.hpp b/include/tmath.hpp
index 0c03b23..c716c3a 100644
--- a/include/tmath.hpp
+++ b/include/tmath.hpp
@@ -31,7 +31,7 @@ DOUBLE sec(DOUBLE x);  // secant
 DOUBLE asec(DOUBLE x);  // arcsecant
 DOUBLE sech(DOUBLE x);  // hyperbolic secant
 
-DOUBLE cosec(DOUBLE x);  // cosecant
+DOUBLE csc(DOUBLE x);  // cosecant
 DOUBLE acsc(DOUBLE x);  // arccosecant
 DOUBLE csch(DOUBLE x);  // hyperbolic cosecant
 
@@ -54,6 +54,8 @@ LONG fac(LONG n);
 DOUBLE facd(LONG n);
 LONG oddfac(LONG n);
 DOUBLE oddfacd(LONG n);
+
+DOUBLE abs(DOUBLE x);
 }
 
 #endif
diff --git a/include/tmath_test.hpp b/include/tmath_test.hpp
new file mode 100644
index 0000000..61e0722
--- /dev/null
+++ b/include/tmath_test.hpp
@@ -0,0 +1,14 @@
+#ifndef _TMATH_TEST_HPP
+#define _TMATH_TEST_HPP
+
+#include <string>
+#include "tmath.hpp"
+
+namespace TMathTest {
+const TMath::DOUBLE DEFAULT_TOLERANCE = 0.001;
+bool equal(TMath::DOUBLE x, TMath::DOUBLE y, TMath::DOUBLE tolerance);
+void assert(TMath::DOUBLE value, TMath::DOUBLE correct, std::string expression);
+void assert(TMath::DOUBLE value, TMath::DOUBLE correct, std::string expression, TMath::DOUBLE tolerance);
+}
+
+#endif
diff --git a/src/tmath.cpp b/src/tmath.cpp
index 20bcc01..390cd0f 100644
--- a/src/tmath.cpp
+++ b/src/tmath.cpp
@@ -21,7 +21,7 @@ TMath::DOUBLE TMath::asin(DOUBLE x)
 		DOUBLE f = facd(odd);
 		DOUBLE p = pow(x, odd);
 		DOUBLE d = p / f * oddf * oddf;
-		delta = d;
+		delta = abs(d);
 		r += p / f * oddf * oddf;
 	}
 	return r;
@@ -56,9 +56,13 @@ TMath::DOUBLE TMath::tan(DOUBLE x)
 TMath::DOUBLE TMath::atan(DOUBLE x)
 {
 	DOUBLE r = 0;
-	for (LONG n = 0; n <= 8; n++)
+	DOUBLE delta = 1;
+	for (LONG n = 0; delta > 1e-4; n++)
 	{
-		r += pow(DOUBLE(-1), n) * pow(x, 2 * n + 1) / (2 * n + 1);
+		LONG odd = 2 * n + 1;
+		DOUBLE d = DOUBLE(pow(-1LL, n)) * pow(x, odd) / DOUBLE(odd);
+		delta = abs(d);
+		r += d;
 	}
 	return r;
 }
@@ -93,7 +97,7 @@ TMath::DOUBLE TMath::sech(DOUBLE x)
 	return 1 / cosh(x);
 }
 /* ================================ COSECANT ======================================== */
-TMath::DOUBLE TMath::cosec(DOUBLE x)
+TMath::DOUBLE TMath::csc(DOUBLE x)
 {
 	return 1 / sin(x);
 }
@@ -139,7 +143,7 @@ TMath::DOUBLE TMath::exp(DOUBLE x)
 	DOUBLE r = 0;
 	for (LONG n = 0; n <= 15L; n++)
 	{
-		r += pow(x, n) / fac(n);
+		r += pow(x, n) / facd(n);
 	}
 	return r;
 }
@@ -223,7 +227,7 @@ TMath::DOUBLE TMath::facd(LONG n) {
 }
 TMath::LONG TMath::oddfac(LONG n) {
 	LONG r = 1;
-	for (LONG i = 3; i <= n; i++) {
+	for (LONG i = 3; i <= n; i += 2) {
 		r *= i;
 	}
 	return r;
@@ -235,6 +239,10 @@ TMath::DOUBLE TMath::oddfacd(LONG n) {
 	}
 	return r;
 }
+TMath::DOUBLE TMath::abs(DOUBLE x) {
+	if (x < 0) return -x;
+	else return x;
+}
 /* ========================================== DEGREE / RADIANT CONVERSION ================================*/
 TMath::DOUBLE TMath::rad(DOUBLE deg)
 {
diff --git a/test/abs/test.cpp b/test/abs/test.cpp
new file mode 100644
index 0000000..37ded0b
--- /dev/null
+++ b/test/abs/test.cpp
@@ -0,0 +1,17 @@
+/*
+   This test checks the abs function.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::abs;
+
+	assert(abs(0.0), 0.0, "abs(0) == 0");
+    assert(abs(1.0), 1.0, "abs(1) == 1");
+    assert(abs(-1.0), 1.0, "abs(-1) == 1");
+
+	return 0;
+}
diff --git a/test/cosecant/test.cpp b/test/cosecant/test.cpp
new file mode 100644
index 0000000..6dd9404
--- /dev/null
+++ b/test/cosecant/test.cpp
@@ -0,0 +1,25 @@
+/*
+   This test checks the cosecant, arccosecant and hyperbolic cosecant function.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::csc;
+	using TMath::acsc;
+	using TMath::csch;
+	using TMath::PI;
+
+	assert(csc(PI / 2.0), 1.0, "csc(PI/2) == 1");
+    assert(csc(-PI / 2.0), -1.0, "csc(-PI/2) == -1");
+
+	assert(acsc(1.1884), 1.0, "acsc(1.1884) == 1");
+    assert(acsc(-1.1884), -1.0, "acsc(-1.1884) == -1");
+
+	assert(csch(0.88137), 1.0, "csch(0.88137) == 1.0");
+    assert(csch(-0.88137), -1.0, "csch(-0.88137) == -1.0");
+
+	return 0;
+}
diff --git a/test/cosine/test.cpp b/test/cosine/test.cpp
new file mode 100644
index 0000000..a56845c
--- /dev/null
+++ b/test/cosine/test.cpp
@@ -0,0 +1,29 @@
+/*
+   This test checks the cosine, arccosine and hyperbolic cosine function.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::cos;
+    using TMath::acos;
+    using TMath::cosh;
+    using TMath::PI;
+
+	assert(cos(0.0), 1, "cos(0) == 1");
+    assert(cos(PI/2.0), 0, "cos(PI/2) == 0");
+    assert(cos(PI), -1, "cos(PI) == -1");
+    assert(cos(PI * 1.5), 0, "cos(PI * 1.5) == 0");
+
+    assert(acos(0), PI * 0.5, "acos(0) == PI/2");
+    assert(acos(0.70711), PI * 0.25, "acos(1/sqrt(2)) == 1/4 PI");
+    assert(acos(-0.70711), PI * 0.75, "acos(1/sqrt(2)) == 3/4 PI");
+
+    assert(cosh(0), 1, "cosh(0) == 1");
+    assert(cosh(1.31696), 2, "cosh(1.31696) == 2");
+    assert(cosh(-1.31696), 2, "cosh(-1.31696) == 2");
+
+	return 0;
+}
diff --git a/test/cotangent/test.cpp b/test/cotangent/test.cpp
new file mode 100644
index 0000000..c2da3de
--- /dev/null
+++ b/test/cotangent/test.cpp
@@ -0,0 +1,26 @@
+/*
+   This test checks the cotangent, arccotangent and hyperbolic cotangent function.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::cot;
+	using TMath::acot;
+	using TMath::coth;
+	using TMath::PI;
+
+	assert(cot(PI / 2.0), 0.0, "cot(PI/2) == 0");
+    assert(cot(-PI / 2.0), 0.0, "cot(-PI/2) == 0");
+
+	assert(acot(0), PI * 0.5, "acot(0) == 1/2 PI");
+    assert(acot(1.0), PI * 0.25, "acot(1) == 1/4 PI");
+    assert(acot(-1.0), PI * 0.75, "acot(-1) == 3/4 PI");
+
+    assert(coth(0.54931), 2.0, "coth(0.54931) == 2.0");
+    assert(coth(-0.54931), -2.0, "coth(-0.54931) == -2.0");
+
+	return 0;
+}
diff --git a/test/exp-log/test.cpp b/test/exp-log/test.cpp
new file mode 100644
index 0000000..711edc9
--- /dev/null
+++ b/test/exp-log/test.cpp
@@ -0,0 +1,39 @@
+/*
+   This test checks the exp, ln, lg, lb and log function.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::exp;
+    using TMath::E;
+    using TMath::ln;
+    using TMath::lb;
+    using TMath::lg;
+    using TMath::log;
+
+	assert(exp(0.0), 1.0, "exp(0) == 1");
+    assert(exp(1.0), E, "exp(1) == e");
+    assert(exp(2.0), E * E, "exp(2) == e*e");
+    assert(exp(-1.0), 1.0 / E, "exp(-1) == 1/e");
+
+    assert(ln(1), 0.0, "ln(1) == 0");
+    assert(ln(E), 1.0, "ln(e) == 1");
+    assert(ln(1.0 / E), -1.0, "ln(1/e) == -1");
+
+    assert(lb(2), 1.0, "lb(2) == 1");
+    assert(lb(4), 2.0, "lb(4) == 2");
+    assert(lb(16), 4.0, "lb(128) == 4");
+
+    assert(lg(10), 1.0, "lg(10) == 1");
+    assert(lg(1), 0.0, "lg(1) == 0");
+    assert(lg(100), 2.0, "lg(100) == 2", 0.01);
+
+    assert(log(E, E), 1.0, "log_e(e) == 1");
+    assert(log(1, E), 0.0, "log_e(1) == 0");
+    assert(log(27, 3), 3.0, "log_3(27) == 3");
+
+	return 0;
+}
diff --git a/test/factorial/test.cpp b/test/factorial/test.cpp
new file mode 100644
index 0000000..7a72c73
--- /dev/null
+++ b/test/factorial/test.cpp
@@ -0,0 +1,38 @@
+/*
+   This test checks the factorial functions;
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::fac;
+    using TMath::facd;
+    using TMath::oddfac;
+    using TMath::oddfacd;
+
+	assert(fac(1), 1, "fac(1) == 1");
+    assert(fac(2), 2, "fac(2) == 2");
+    assert(fac(3), 6, "fac(3) == 6");
+    assert(fac(4), 24, "fac(4) == 24");
+
+    assert(facd(1), 1.0, "facd(1) == 1.0");
+    assert(facd(2), 2.0, "facd(2) == 2.0");
+    assert(facd(3), 6.0, "facd(3) == 6.0");
+    assert(facd(4), 24.0, "facd(4) == 24.0");
+
+    assert(oddfac(1), 1, "oddfac(1) == 1");
+    assert(oddfac(2), 1, "oddfac(2) == 1");
+    assert(oddfac(3), 3, "oddfac(3) == 3");
+    assert(oddfac(4), 3, "oddfac(4) == 3");
+    assert(oddfac(5), 15, "oddfac(5) == 15");
+
+    assert(oddfacd(1), 1.0, "oddfacd(1) == 1.0");
+    assert(oddfacd(2), 1.0, "oddfacd(2) == 1.0");
+    assert(oddfacd(3), 3.0, "oddfacd(3) == 3.0");
+    assert(oddfacd(4), 3.0, "oddfacd(4) == 3.0");
+    assert(oddfacd(5), 15.0, "oddfacd(5) == 15.0");
+
+	return 0;
+}
diff --git a/test/power/test.cpp b/test/power/test.cpp
new file mode 100644
index 0000000..e37e858
--- /dev/null
+++ b/test/power/test.cpp
@@ -0,0 +1,26 @@
+/*
+   This test checks the power functions.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::pow;
+
+    assert(pow(2.0L, 2.0L), 4.0L, "pow(2, 2) == 4");
+    assert(pow(2.0L, 0.5L), 1.41421356237L, "pow(2, 0.5) == 1.414");
+    assert(pow(2.0L, -1.0L), 0.5L, "pow(2, -1) == 0.5");
+    assert(pow(2.0L, 0.0L), 1.0L, "pow(2, 0) == 1");
+
+    assert(pow(2LL, 2LL), 4LL, "pow(2, 2) == 4");
+    assert(pow(1LL, -1LL), 1LL, "pow(1, -1) == 1");
+    assert(pow(2LL, 0LL), 1LL, "pow(2, 0) == 1");
+
+    assert(pow(0.5L, 2LL), 0.25L, "pow(0.5, 2) == 0.25");
+    assert(pow(0.5L, -1LL), 2.0L, "pow(0.5, -1) == 2");
+    assert(pow(0.5L, 0LL), 1.0L, "pow(0.5, 0) == 1");
+
+	return 0;
+}
diff --git a/test/rad-deg/test.cpp b/test/rad-deg/test.cpp
new file mode 100644
index 0000000..5bfa6bc
--- /dev/null
+++ b/test/rad-deg/test.cpp
@@ -0,0 +1,31 @@
+/*
+   This test checks the rad-deg conversion functions.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::rad;
+    using TMath::deg;
+    using TMath::PI;
+
+	assert(rad(0), 0.0, "rad(0) == 0");
+    assert(rad(45), PI * 0.25, "rad(45) == 1/4 PI");
+    assert(rad(90), PI * 0.5, "rad(90) == 1/2 PI");
+    assert(rad(135), PI * 0.75, "rad(135) == 3/4 PI");
+    assert(rad(180), PI, "rad(180) == PI");
+    assert(rad(270), PI * 1.5, "rad(270) == 3/2 PI");
+    assert(rad(360), PI * 2.0, "rad(360) == 2 PI");
+
+    assert(deg(0), 0, "deg(0) == 0");
+    assert(deg(PI * 0.25), 45, "deg(1/4 PI) == 45");
+    assert(deg(PI * 0.5), 90, "deg(1/2 PI) == 90");
+    assert(deg(PI * 0.75), 135, "deg(3/4 PI) == 135");
+    assert(deg(PI), 180, "deg(PI) == 180");
+    assert(deg(PI * 1.5), 270, "deg(3/2 PI) == 270");
+    assert(deg(PI * 2.0), 360, "deg(2 * PI) == 360");
+
+	return 0;
+}
diff --git a/test/roots/test.cpp b/test/roots/test.cpp
new file mode 100644
index 0000000..d6235e5
--- /dev/null
+++ b/test/roots/test.cpp
@@ -0,0 +1,21 @@
+/*
+   This test checks the root functions.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::root;
+    using TMath::sqrt;
+
+    assert(root(27.0L, 3.0L), 3.0L, "root(27, 3) == 3");
+    assert(root(1.0L, 1.0L), 1.0L, "root(1, 1) == 1");
+
+    assert(sqrt(4.0L), 2.0L, "sqrt(4) == 2");
+    assert(sqrt(9.0L), 3.0L, "sqrt(9) == 3");
+    assert(sqrt(1.0L), 1.0L, "sqrt(1) == 1");
+
+	return 0;
+}
diff --git a/test/secant/test.cpp b/test/secant/test.cpp
new file mode 100644
index 0000000..38ab817
--- /dev/null
+++ b/test/secant/test.cpp
@@ -0,0 +1,27 @@
+/*
+   This test checks the secant, arcsecant and hyperbolic secant function.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::sec;
+	using TMath::asec;
+	using TMath::sech;
+	using TMath::PI;
+
+	assert(sec(0), 1.0, "sec(0) == 1");
+    assert(sec(-PI), -1.0, "sec(-PI) == -1");
+    assert(sec(PI), -1.0, "sec(PI) == -1");
+
+    assert(asec(1.41421356237L), PI * 0.25, "asec(sqrt(2)) == 1/4 PI");
+    assert(asec(-1.41421356237L), PI * 0.75, "asec(-sqrt(2)) == 3/4 PI");
+
+    assert(sech(0), 1.0, "sech(0) == 1");
+    assert(sech(1.31696), 0.5, "sech(1.31696) == 0.5");
+    assert(sech(-1.31696), 0.5, "sech(-1.31696) == 0.5");
+
+	return 0;
+}
diff --git a/test/sine/test.cpp b/test/sine/test.cpp
new file mode 100644
index 0000000..8ea9ab7
--- /dev/null
+++ b/test/sine/test.cpp
@@ -0,0 +1,30 @@
+/*
+   This test checks the sine, arcsine and hyperbolic sine function.
+ */
+
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::sin;
+	using TMath::asin;
+	using TMath::sinh;
+	using TMath::PI;
+
+	assert(sin(0), 0, "sin(0) == 0");
+	assert(sin(PI/2.0), 1.0, "sin(PI/2) == 1");
+	assert(sin(PI), 0.0, "sin(PI) == 0");
+	assert(sin(1.5 * PI), -1.0, "sin(1.5 * PI) == -1");
+	assert(sin(2.0 * PI), 0.0, "sin(2 * PI) == 0");
+
+	assert(asin(0), 0, "asin(0) == 0");
+	assert(asin(0.5), PI/6.0, "asin(0.5) == PI/6");
+	assert(asin(-0.5), -PI/6.0, "asin(-0.5) == -PI/6");
+
+	assert(sinh(0), 0, "sinh(0) == 0");
+	assert(sinh(0.88137), 1.0, "sinh(0.88137) == 1");
+	assert(sinh(-0.88137), -1.0, "sinh(-0.88137) == -1");
+
+	return 0;
+}
diff --git a/test/tangent/test.cpp b/test/tangent/test.cpp
new file mode 100644
index 0000000..de0741e
--- /dev/null
+++ b/test/tangent/test.cpp
@@ -0,0 +1,28 @@
+/*
+   This test checks the tangent, arctangent and hyperbolic tangent function.
+ */
+ 
+#include "tmath.hpp"
+#include "tmath_test.hpp"
+
+int main(int argc, char const *argv[]) {
+	using TMathTest::assert;
+	using TMath::tan;
+	using TMath::atan;
+	using TMath::tanh;
+	using TMath::PI;
+
+	assert(tan(0), 0, "tan(0) == 0");
+	assert(tan(PI/4.0), 1.0, "tan(PI/4) == 1");
+	assert(tan(-PI/4.0), -1.0, "tan(-PI/4) == -1");
+
+	assert(atan(0), 0, "atan(0) == 0");
+	assert(atan(1), PI/4.0, "atan(1) == PI/4");
+	assert(atan(-1), -PI/4.0, "atan(-1) == -PI/4");
+
+	assert(tanh(0), 0, "tanh(0) == 0");
+	assert(tanh(0.549306), 0.5, "tanh(0.549306) == 0.5");
+	assert(tanh(-0.549306), -0.5, "tanh(-0.549306) == -0.5");
+
+	return 0;
+}
diff --git a/test/tmath_test.cpp b/test/tmath_test.cpp
new file mode 100644
index 0000000..2b661d2
--- /dev/null
+++ b/test/tmath_test.cpp
@@ -0,0 +1,24 @@
+#include "tmath_test.hpp"
+#include <iostream>
+#include <cstdlib>
+
+bool TMathTest::equal(TMath::DOUBLE x, TMath::DOUBLE y, TMath::DOUBLE tolerance) {
+	if (x - tolerance <= y && x + tolerance >= y) return true;
+	else return false;
+}
+
+void TMathTest::assert(TMath::DOUBLE value, TMath::DOUBLE correct, std::string expression) {
+    assert(value, correct, expression, TMathTest::DEFAULT_TOLERANCE);
+}
+
+void TMathTest::assert(TMath::DOUBLE value, TMath::DOUBLE correct, std::string expression, TMath::DOUBLE tolerance) {
+    if (!equal(value, correct, tolerance)) {
+        std::cout << "Assert: " << expression << " failed" << std::endl;
+		std::cout << value << " is not nearly equal " << correct << std::endl;
+        exit(1);
+    } else {
+		double deviation = value - correct;
+		deviation = deviation < 0 ? -deviation : deviation;
+		std::cout << "Test (" << expression << ") passed with deviation of " << deviation << std::endl;
+	}
+}