Task 8 is done

2025.04.18/08Ex/Makefile

@@ -0,0 +1,42 @@
+WFLAGS = -fstack-protector-all -W -Wall -Wextra -Wunused \
+-Wempty-body -Wlogical-op -Wold-style-declaration -Wmissing-parameter-type \
+-Wignored-qualifiers -Winit-self -Wshadow -Wtype-limits \
+-Wpointer-arith -Wformat-security -Wmissing-format-attribute -Wformat=1 \
+-Wdeclaration-after-statement -Wbad-function-cast -Wnested-externs \
+-Wmissing-prototypes -Wmissing-declarations -Wold-style-definition \
+-Wcast-align -Werror -pedantic -pedantic-errors -Wfloat-equal \
+-Wwrite-strings -Wno-long-long -std=gnu99 -Wstrict-prototypes \
+-Wmissing-field-initializers -Wpointer-sign
+
+CFLAGS = -std=gnu99 -mfpmath=sse -O3
+
+ifeq ($(OS),Windows_NT)
+	EXE = exe
+	CLEAN = del
+	LFLAGS = -lssp -lm
+else
+	EXE = out
+	CLEAN = rm -f
+	LFLAGS = -lm
+endif
+
+TARGET = a08.$(EXE)
+OBJ = main.o solve.o contin_func.o
+
+%.o: %.c
+	gcc $(CFLAGS) $(WFLAGS) -c $< -o $@
+
+$(TARGET): $(OBJ)
+	gcc $^ -o $@ $(LFLAGS)
+
+# Отладочная сборка (gdb)
+gdb: CFLAGS = -mfpmath=sse -std=gnu99 -g -O0
+gdb: clean $(TARGET)
+
+# Профилировочная сборка (gprof)
+prof: CFLAGS = -std=gnu99 -mfpmath=sse -pg -O3
+prof: LFLAGS = -lm -pg
+prof: clean $(TARGET)
+
+clean:
+	$(CLEAN) *.o *$(EXE)

2025.04.18/08Ex/contin_func.c

@@ -0,0 +1,42 @@
+#include "contin_func.h"
+
+#include <math.h>
+#include <float.h>
+
+double fln (const double x, const double eps)
+{
+	const double z = (x - 1) / (x + 1);
+	double value = 0;
+	double monom = z, el = z;
+	int i = 1;
+
+	while (el - eps > DBL_EPSILON)
+	{
+		value += el;
+
+		i+=2;
+		monom *= z*z;
+		el = monom / i;
+	}
+
+	return 2 * value;
+}
+
+double sln (const double x, const double eps)
+{
+	const double z = x - 1;
+	double value = 0;
+	double monom = z, el = z;
+	int i = 1;
+
+	while (fabs(el) - eps > DBL_EPSILON)
+	{
+		value += el;
+
+		i++;
+		monom *= -z;
+		el = monom / i;
+	}
+
+	return value;
+}

2025.04.18/08Ex/contin_func.h

@@ -0,0 +1,7 @@
+#ifndef CONTIN_FUNC_H
+#define CONTIN_FUNC_H
+
+double fln (const double x, const double eps);
+double sln (const double x, const double eps);
+
+#endif

2025.04.18/08Ex/io_status.h

@@ -0,0 +1,9 @@
+#ifndef IO_STATUS_H
+#define IO_STATUS_H
+
+#define ERR_MEM	"Error: Not enough memory!"
+#define ERR_OPEN "Error: Cannot open file"
+#define ERR_READ "Error: Cannot read file"
+#define ERR_FUNC "Error: Algorithm is not applicable!"
+
+#endif

2025.04.18/08Ex/main.c

@@ -0,0 +1,34 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <math.h>
+
+#include "io_status.h"
+#include "solve.h"
+
+/* ./a.out x eps */
+int main(int argc, char *argv[])
+{
+	double x, eps, t, r1 = 0, r2 = 0;
+	int task = 8;
+
+	if (
+			!((argc == 3) && 
+			((sscanf(argv[1], "%le", &x) == 1) && x > 0) &&
+			((sscanf(argv[2], "%le", &eps) == 1) && eps > 0))
+	) {
+		fprintf(stderr, "Usage: %s x eps\n", argv[0]);
+		return 1;
+	}
+
+	t = clock();
+	r1 = dln(x, eps);
+	t = (clock() - t) / CLOCKS_PER_SEC;
+
+	r2 = fabs(r1 - log(x));
+
+	printf("%s : Task = %d Result = %e Residual = %e Elapsed = %.2f\n", argv[0], task, r1, r2, t);
+
+	return 0;
+}
+

2025.04.18/08Ex/solve.c

@@ -0,0 +1,30 @@
+#include "solve.h"
+#include "contin_func.h"
+
+#include <stdlib.h>
+#include <stdbool.h>
+#include <math.h>
+#include <float.h>
+
+double dln (double x, const double eps)
+{
+	double value = 0;
+	int b = 0;
+
+	while (x - 2 > DBL_EPSILON)
+	{
+		x *= 0.5;
+		b++;
+	}
+	
+	while (x - 1 <= DBL_EPSILON)
+	{
+		x *= 2;
+		b--;
+	}
+	
+	value = fln(x, eps);
+
+	value += b * M_LN2;
+	return value;
+}

2025.04.18/08Ex/solve.h

@@ -0,0 +1,6 @@
+#ifndef SOLVE_H
+#define SOLVE_H
+
+double dln (double x, const double eps);
+
+#endif