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--- a/lib/ipmi_sdr.c
+++ b/lib/ipmi_sdr.c
@@ -4399,3 +4399,146 @@ ipmi_sdr_main(struct ipmi_intf *intf, in
return rc;
}
+
+/* cbrt.c
+ *
+ * Cube root
+ *
+ *
+ *
+ * SYNOPSIS:
+ *
+ * double x, y, cbrt();
+ *
+ * y = cbrt( x );
+ *
+ *
+ *
+ * DESCRIPTION:
+ *
+ * Returns the cube root of the argument, which may be negative.
+ *
+ * Range reduction involves determining the power of 2 of
+ * the argument. A polynomial of degree 2 applied to the
+ * mantissa, and multiplication by the cube root of 1, 2, or 4
+ * approximates the root to within about 0.1%. Then Newton's
+ * iteration is used three times to converge to an accurate
+ * result.
+ *
+ *
+ *
+ * ACCURACY:
+ *
+ * Relative error:
+ * arithmetic domain # trials peak rms
+ * DEC -10,10 200000 1.8e-17 6.2e-18
+ * IEEE 0,1e308 30000 1.5e-16 5.0e-17
+ *
+ */
+/* cbrt.c */
+
+/*
+Cephes Math Library Release 2.8: June, 2000
+Copyright 1984, 1991, 2000 by Stephen L. Moshier
+*/
+
+
+static double CBRT2 = 1.2599210498948731647672;
+static double CBRT4 = 1.5874010519681994747517;
+static double CBRT2I = 0.79370052598409973737585;
+static double CBRT4I = 0.62996052494743658238361;
+
+#ifdef ANSIPROT
+extern double frexp ( double, int * );
+extern double ldexp ( double, int );
+extern int isnan ( double );
+extern int isfinite ( double );
+#else
+/*
+double frexp(), ldexp();
+int isnan(double), isfinite(double);
+*/
+#endif
+
+double cbrt(double x)
+{
+/* double x; */
+int e, rem, sign;
+double z;
+
+#ifdef NANS
+if( isnan(x) )
+ return x;
+#endif
+#ifdef INFINITIES
+if( !isfinite(x) )
+ return x;
+#endif
+if( x == 0 )
+ return( x );
+if( x > 0 )
+ sign = 1;
+else
+ {
+ sign = -1;
+ x = -x;
+ }
+
+z = x;
+/* extract power of 2, leaving
+ * mantissa between 0.5 and 1
+ */
+x = frexp( x, &e );
+
+/* Approximate cube root of number between .5 and 1,
+ * peak relative error = 9.2e-6
+ */
+x = (((-1.3466110473359520655053e-1 * x
+ + 5.4664601366395524503440e-1) * x
+ - 9.5438224771509446525043e-1) * x
+ + 1.1399983354717293273738e0 ) * x
+ + 4.0238979564544752126924e-1;
+
+/* exponent divided by 3 */
+if( e >= 0 )
+ {
+ rem = e;
+ e /= 3;
+ rem -= 3*e;
+ if( rem == 1 )
+ x *= CBRT2;
+ else if( rem == 2 )
+ x *= CBRT4;
+ }
+
+
+/* argument less than 1 */
+
+else
+ {
+ e = -e;
+ rem = e;
+ e /= 3;
+ rem -= 3*e;
+ if( rem == 1 )
+ x *= CBRT2I;
+ else if( rem == 2 )
+ x *= CBRT4I;
+ e = -e;
+ }
+
+/* multiply by power of 2 */
+x = ldexp( x, e );
+
+/* Newton iteration */
+x -= ( x - (z/(x*x)) )*0.33333333333333333333;
+#ifdef DEC
+x -= ( x - (z/(x*x)) )/3.0;
+#else
+x -= ( x - (z/(x*x)) )*0.33333333333333333333;
+#endif
+
+if( sign < 0 )
+ x = -x;
+return(x);
+}
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