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Breadcrumbs go here --> </ul> </div> <div class="toolbuttons toolblock"> <ul> <li id="smallA" class="t_button">A</li> <li id="medA" class="t_button active">A</li> <li id="bigA" class="t_button">A</li> <li id="print" class="t_button"><a href="javascript:this.print();"> <span>Print</span></a></li> </ul> </div> </div> <div class="content mainContent"> <h1 class="title"><QtCore/qmath.h> - Math Functions</h1> <span class="subtitle"></span> <!-- $$$<QtCore/qmath.h>-brief --> <p>The <<a href="qtcore.html">QtCore</a>/qmath.h> header provides various math functions. <a href="#details">More...</a></p> <!-- @@@<QtCore/qmath.h> --> <ul> </ul> <a name="Functionsx"></a> <h2>Functions</h2> <table class="alignedsummary"> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qAcos">qAcos</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qAsin">qAsin</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qAtan2">qAtan2</a></b> ( qreal <i>y</i>, qreal <i>x</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qAtan">qAtan</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qCeil">qCeil</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qCos">qCos</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qExp">qExp</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qFloor">qFloor</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qLn">qLn</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qPow">qPow</a></b> ( qreal <i>x</i>, qreal <i>y</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qSin">qSin</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qSqrt">qSqrt</a></b> ( qreal <i>v</i> )</td></tr> <tr><td class="memItemLeft topAlign rightAlign"> qreal </td><td class="memItemRight bottomAlign"><b><a href="qtcore-qmath-h.html#qTan">qTan</a></b> ( qreal <i>v</i> )</td></tr> </table> <!-- $$$<QtCore/qmath.h>-description --> <div class="descr"> <a name="details"></a> </div> <!-- @@@<QtCore/qmath.h> --> <h2>Function Documentation</h2> <!-- $$$qAcos[overload1]$$$qAcosqreal --> <h3 class="fn"><a name="qAcos"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qAcos</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Returns the arccosine of <i>v</i> as an angle in radians. Arccosine is the inverse operation of cosine.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qAtan">qAtan</a>(), <a href="qtcore-qmath-h.html#qAsin">qAsin</a>(), and <a href="qtcore-qmath-h.html#qCos">qCos</a>().</p> <!-- @@@qAcos --> <!-- $$$qAsin[overload1]$$$qAsinqreal --> <h3 class="fn"><a name="qAsin"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qAsin</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Returns the arcsine of <i>v</i> as an angle in radians. Arcsine is the inverse operation of sine.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qSin">qSin</a>(), <a href="qtcore-qmath-h.html#qAtan">qAtan</a>(), and <a href="qtcore-qmath-h.html#qAcos">qAcos</a>().</p> <!-- @@@qAsin --> <!-- $$$qAtan2[overload1]$$$qAtan2qrealqreal --> <h3 class="fn"><a name="qAtan2"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qAtan2</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>y</i>, <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>x</i> )</h3> <p>Returns the arctangent of a point specified by the coordinates <i>y</i> and <i>x</i>. This function will return the angle (argument) of that point.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qAtan">qAtan</a>().</p> <!-- @@@qAtan2 --> <!-- $$$qAtan[overload1]$$$qAtanqreal --> <h3 class="fn"><a name="qAtan"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qAtan</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Returns the arctangent of <i>v</i> as an angle in radians. Arctangent is the inverse operation of tangent.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qTan">qTan</a>(), <a href="qtcore-qmath-h.html#qAcos">qAcos</a>(), and <a href="qtcore-qmath-h.html#qAsin">qAsin</a>().</p> <!-- @@@qAtan --> <!-- $$$qCeil[overload1]$$$qCeilqreal --> <h3 class="fn"><a name="qCeil"></a><span class="type">int</span> <span class="name">qCeil</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Return the ceiling of the value <i>v</i>.</p> <p>The ceiling is the smallest integer that is not less than <i>v</i>. For example, if <i>v</i> is 41.2, then the ceiling is 42.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qFloor">qFloor</a>().</p> <!-- @@@qCeil --> <!-- $$$qCos[overload1]$$$qCosqreal --> <h3 class="fn"><a name="qCos"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qCos</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Returns the cosine of an angle <i>v</i> in radians.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qSin">qSin</a>() and <a href="qtcore-qmath-h.html#qTan">qTan</a>().</p> <!-- @@@qCos --> <!-- $$$qExp[overload1]$$$qExpqreal --> <h3 class="fn"><a name="qExp"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qExp</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Returns the exponential function of <tt>e</tt> to the power of <i>v</i>.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qLn">qLn</a>().</p> <!-- @@@qExp --> <!-- $$$qFloor[overload1]$$$qFloorqreal --> <h3 class="fn"><a name="qFloor"></a><span class="type">int</span> <span class="name">qFloor</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Return the floor of the value <i>v</i>.</p> <p>The floor is the largest integer that is not greater than <i>v</i>. For example, if <i>v</i> is 41.2, then the floor is 41.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qCeil">qCeil</a>().</p> <!-- @@@qFloor --> <!-- $$$qLn[overload1]$$$qLnqreal --> <h3 class="fn"><a name="qLn"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qLn</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Returns the natural logarithm of <i>v</i>. Natural logarithm uses base e.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qExp">qExp</a>().</p> <!-- @@@qLn --> <!-- $$$qPow[overload1]$$$qPowqrealqreal --> <h3 class="fn"><a name="qPow"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qPow</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>x</i>, <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>y</i> )</h3> <p>Returns the value of <i>x</i> raised to the power of <i>y</i>. That is, <i>x</i> is the base and <i>y</i> is the exponent.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qSqrt">qSqrt</a>().</p> <!-- @@@qPow --> <!-- $$$qSin[overload1]$$$qSinqreal --> <h3 class="fn"><a name="qSin"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qSin</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Returns the sine of the angle <i>v</i> in radians.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qCos">qCos</a>() and <a href="qtcore-qmath-h.html#qTan">qTan</a>().</p> <!-- @@@qSin --> <!-- $$$qSqrt[overload1]$$$qSqrtqreal --> <h3 class="fn"><a name="qSqrt"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qSqrt</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Returns the square root of <i>v</i>. This function returns a NaN if <i>v</i> is a negative number.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qPow">qPow</a>().</p> <!-- @@@qSqrt --> <!-- $$$qTan[overload1]$$$qTanqreal --> <h3 class="fn"><a name="qTan"></a><span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <span class="name">qTan</span> ( <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> <i>v</i> )</h3> <p>Returns the tangent of an angle <i>v</i> in radians.</p> <p><b>See also </b><a href="qtcore-qmath-h.html#qSin">qSin</a>() and <a href="qtcore-qmath-h.html#qCos">qCos</a>().</p> <!-- @@@qTan --> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2015 The Qt Company Ltd. 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