{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "## Math Functions and Trigonometry" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "### Useful Functions" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "|Operation|Matlab Example|\n", "|---|\n", "|Natural Logarithm|log(10)|\n", "|Logarithm Base 10|log10(10)|\n", "|Remainder (modulus)|mod(8,3)|\n", "|sin(*arg in rads*)|sin(2)|\n", "|sin(*arg in degs*)|sind(90)|\n", "|cos(*radians*)|cos(2)|\n", "|cos(*degrees*)|cosd(45)|\n", "|tan(*rads*)|tan(2)|\n", "|exponential $e^n$|exp(*n*)|\n", "|square root|sqrt(4)|\n", "|factorial $n!$|factorial(*n*)|\n", "|nth root $\\sqrt[n]{x}$|nthroot(x,n)|" ] }, { "cell_type": "code", "execution_count": 31, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 120\n" ] } ], "source": [ "% factorial - 5! is not used\n", "factorial(5)" ] }, { "cell_type": "code", "execution_count": 32, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 3\n" ] } ], "source": [ "% square root\n", "sqrt(9)" ] }, { "cell_type": "code", "execution_count": 33, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 2.2361\n" ] } ], "source": [ "sqrt(5)" ] }, { "cell_type": "code", "execution_count": 34, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 3\n" ] } ], "source": [ "9^(1/2)" ] }, { "cell_type": "code", "execution_count": 36, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 3\n" ] } ], "source": [ "% Nth Root: nthroot(X, n)\n", "% returns the nth root of X\n", "nthroot(27, 3)" ] }, { "cell_type": "code", "execution_count": 39, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", " \n", "89333^(1/2)\n" ] } ], "source": [ "sym(sqrt(89333))" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "#### Trigonometry" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "*NOTE: MATLAB interprets arguments to trig functions as radians - must convert to degrees if thats what you want!*" ] }, { "cell_type": "code", "execution_count": 3, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 0.8509\n" ] } ], "source": [ "% some trig examples \n", "deg = sym('deg');\n", "rad = sym('rad');\n", "deg = rad*180/pi; % convert rad2deg\n", "rad = deg*pi/180; % convert deg2rad\n", "\n", "sin(45)" ] }, { "cell_type": "code", "execution_count": 7, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 0.8061\n" ] } ], "source": [ "sin(45*180/pi)" ] }, { "cell_type": "code", "execution_count": 9, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 1.0607\n" ] } ], "source": [ "log10(11.5)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "#### Log and Exp" ] }, { "cell_type": "code", "execution_count": 15, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 1.0000\n" ] } ], "source": [ "% MATLAB uses log base e (natural log) by default\n", "% e = 2.7183, so...\n", "log(2.7183)" ] }, { "cell_type": "code", "execution_count": 16, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 2\n" ] } ], "source": [ "% to change to base:\n", "log10(100)" ] }, { "cell_type": "code", "execution_count": 17, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 2.7183\n" ] } ], "source": [ "% for exponential, we use the exp() function\n", "exp(1)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "#### Complex Numbers" ] }, { "cell_type": "code", "execution_count": 18, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 0.0000 + 1.0000i\n" ] } ], "source": [ "% MATLAB recognizes both i and j as complex numbers\n", "i" ] }, { "cell_type": "code", "execution_count": 19, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 0.0000 + 1.0000i\n" ] } ], "source": [ "j" ] }, { "cell_type": "code", "execution_count": 20, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " -1\n" ] } ], "source": [ "i * i" ] }, { "cell_type": "code", "execution_count": 22, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 0.0000 + 1.0000i\n" ] } ], "source": [ "sqrt(-1)" ] }, { "cell_type": "code", "execution_count": 23, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 6.0000 - 8.0000i\n" ] } ], "source": [ "(1-4i)+(5-4i)" ] }, { "cell_type": "code", "execution_count": 25, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 0.0000 + 2.0000i\n" ] } ], "source": [ "2*j" ] }, { "cell_type": "code", "execution_count": 26, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 19.0000 + 7.0000i\n" ] } ], "source": [ "% variables can be assigned as complex\n", "a = 3 - i;\n", "b = 5 + 4i;\n", "a*b" ] }, { "cell_type": "code", "execution_count": 27, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " -1.1333e+03 + 1.6569e+02i\n" ] } ], "source": [ "a^b" ] }, { "cell_type": "code", "execution_count": 39, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 5\n" ] } ], "source": [ "% the magnitude of complex can also be found with abs()\n", "a = 4 - 3i;\n", "abs(a)" ] }, { "cell_type": "code", "execution_count": 34, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " -0.7854\n" ] } ], "source": [ "% the angle is also found (in radians)\n", "angle(a)" ] }, { "cell_type": "code", "execution_count": 35, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 57\n", "\n", "\n", "ans =\n", "\n", " -872\n" ] } ], "source": [ "% real()/imag() are used to get the respective part of a complex #\n", "a = 57 - 872i;\n", "real(a)\n", "imag(a)" ] }, { "cell_type": "code", "execution_count": 36, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 5.7000e+01 + 8.7200e+02i\n" ] } ], "source": [ "% complex conjugates are found 2 ways:\n", "conj(a)" ] }, { "cell_type": "code", "execution_count": 37, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 5.7000e+01 + 8.7200e+02i\n" ] } ], "source": [ "a'" ] }, { "cell_type": "code", "execution_count": 38, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "ans =\n", "\n", " 3.0000 + 9.0000i\n" ] } ], "source": [ "% lastly, a complex number can be constructed using a function\n", "complex(3,9)" ] } ], "metadata": { "kernelspec": { "display_name": "Matlab", "language": "matlab", "name": "matlab" }, "language_info": { "codemirror_mode": "octave", "file_extension": ".m", "help_links": [ { "text": "MetaKernel Magics", "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md" } ], "mimetype": "text/x-matlab", "name": "matlab", "version": "0.8.0" } }, "nbformat": 4, "nbformat_minor": 0 }