1.4. Special symbols and operations in Mathematica

SymbolFunctionExample
 
%Result from the last OutN[%,50] - Repeats the previous calculation with an accuracy of 50 symbols
 
%%Result from the second-last Out    
 
%%% Result from the third-last Out    
 
%nResult from Out[n]%20 - Repeats the 20th Out
 
  ,Universal separatorPlot[ 3 FormBox[StyleBox[Sty ... Alignments -> {Left}, ColumnLines -> 0.5, RowMinHeight -> 1.}], TableMasterGrid], TraditionalForm]+4, {x,1,5}]
 
  ;Separator for expressions on one line and prohibits displaying the result on the screenx=223;   -Will not visualize Out
 
  .A decimal point in presenting constants;
Symbol for invalidation of a variable;
Symbol for multiplication of matrices		-22.345
x1=.    The variable x1 is invalidated
m.n
 
  =Symbol for appropriationа12=1.345π
 
  :=Defining a function or rulef[x_]:=Sin[t]
 
  /.Temporary change of values for the current calculationCos[ 2 FormBox[StyleBox[Sty ... Alignments -> {Left}, ColumnLines -> 0.5, RowMinHeight -> 1.}], TableMasterGrid], TraditionalForm]]  /. x->3a    
-The result is: cos(9 4 FormBox[StyleBox[StyleBox[Sty ... Alignments -> {Left}, ColumnLines -> 0.5, RowMinHeight -> 1.}], TableMasterGrid], TraditionalForm])
 
  -> Arrow for replacement of a value or ruleArcCos[ 2 FormBox[StyleBox[Sty ... Alignments -> {Left}, ColumnLines -> 0.5, RowMinHeight -> 1.}], TableMasterGrid], TraditionalForm]] /. x->0.5
 
  //NNumeric result for the expression before itπ //N      - The result is:   3.14159
 
  (  ) Brackets for arithmetic and logic operations. h=( 7- 5 FormBox[StyleBox[St ... Alignments -> {Left}, ColumnLines -> 0.5, RowMinHeight -> 1.}], TableMasterGrid], TraditionalForm]/ (1-3 ( 2+ 3 FormBox[StyleBox[StyleBox[Sty ... Alignments -> {Left}, ColumnLines -> 0.5, RowMinHeight -> 1.}], TableMasterGrid], TraditionalForm]))      
 
  [  ]   Brackets for the arguments of a function.D[Sin[x-4]]  
 
  {  }Brackets for list elements (row, matrix, graph arguments etc.).m={-1, 0, 6, 4 ,1 }
- Assigns vector m with 6 coordinates
 
  [ [    ] ]Brackets for extraction of elements or indexesm[ [ 3 ] ]     -  Third element of m
 
  (*      *)Brackets for comments(*   Can be placed anywhere *)
 
  
  ^
  *  or space
  /
  +    -   		Symbols for arithmetic operations:
power
multiplication
division (and a fraction line)
addition, subtraction
a=2π / 7
b=a*c / (3-x^3)
 
  
  ==
  !=
  >   >=
  <=   < 		Comparison symbols:
Equal,
different
Larger, Larger/Equal etc.		Used for checking identities, for solving equations and recording of complex logic expressions
 

  !
  &&
  ||
  Xor[p,q,...]  		Logical operations:
Logical ‘Not’ or factorial symbol
Logical ‘And’
Logical ‘Or’
Exclusive ‘Or’		Used for solving calculations, for logical verification etc.
  ! (a && b<2)
 
  <<Symbol for reading an outside file, i.e. including an add-on package of functions<<Graphics`Shapes`
<<name_ of_ the_ file
 
  >>Symbol for taking out results to a file Expression >> name_of_the_file
 
  >>>Add to fileExpression >>> name_of_the_file
 
  !!Reads the text in the fileExpression >> f1
!!f1