“《超越学科的认知基础》2015张世超学习报告第六周”版本间的差异

2015年10月27日 (二) 06:54的版本

Mathematica[1]

Mathematica 指令表
操作	指令
enter i	type esc-ii-esc
enter square root	control -2
enter "e"	esc-ee-esc
power	control-6
fraction	control-forwardslash
evaluate	shift-return
new line	return
alias for the last output expression	%
make substitution	/.
Expand	Expand[ ]
Simplify x²+(2x²+sin(x))	Simplify[x²+(2x²+sin[x])]
Factorise	Factor[x²-1]
Evaluate πto decimal places	N[π，100]
poly=1+3x+5x³+6sin[x]	poly=1+3x+5x³+6sin[x]
extract the coefficient	Coefficient[poly,x²]
Solve the equation z=x²+1 for x (remember to use == not =)	z==x²+1
Solve the system of equations:x+y+z=1 x-y=2	Solve[x+y+z==1&&x-y==2,{x,y,z}]
Determinant	Det[A]
Mutiply the matrix A by the Vector v.	A.v %//MatrixForm
Inverse	Inverse[A]//MatrixForm
MatrixPower	[A,2]//MatrixForm or A²//MatrixForm
Transpose	Transpose[A]//MatrixForm
Extract	A1//MatrixForm
Make a 10×10 matrix and automatically populate if with a formula.	M=Table[i*j+sin[i+j},{i,1,10},{j,1,10}];M//MatrixForm
data={1,2,3,4,5}	av2[v_]:=Total[v]/Length[v];av2[data]
Function
Define a function;f[x_]:=cos[x]+sin[x];g[x_]:=cos[x]-2;	Evaluate+for x =1;N[f[1],500]
Average:Write a function av(v)	evaluate it for {1,2,3,4,5}
Plotting
Plot the function sin(x) in the range 0<x<5	Plot [sin[x],{x,0,5}]
Superimpose the plots of sin(x) and cos(x)	Plot[{sin[x],cos[x]},{x,0,10}]
Make a 3D plot of sin(x)cosxy over the range 0<x<5,0<y<5	Plot 3D[sin[x]Cos[y],{x,0,5},{y,0,5}]
Change the font size and disale the mesh	Plot3D

@@ 第60行： / 第60行： @@
 |z==x²+1
 |-
-rowspan="2"|Solve the system of equations:x+y+z=1 x-y=2
+|Solve the system of equations:x+y+z=1 x-y=2
-rowspan="2"|Solve[x+y+z==1&&x-y==2,{x,y,z}]
+|Solve[x+y+z==1&&x-y==2,{x,y,z}]
 |-
 |Determinant