SetDirectory[NotebookDirectory[]]

FileNames[]

data=Import["koeficientyReal.xls"][[1]];

data2=Drop[data,1];
Amat=data2[[All,;;-2]];
b=data2[[All,-1]];
Inverse[Amat].b
LinearSolve[Amat,b]

data2//Dimensions

vars=ToExpression["x"<>ToString[#]]&/@Range[10]

ClearAll[x]

(Subscript[x, #])&/@Range[10]

LinearSolve[Amat,b]//AbsoluteTiming

Solve[Thread[Amat.vars==b],vars]//AbsoluteTiming

dataKomp=Import["koeficientyKomplex.xls"][[1]];

dataKomp[[;;,-2;;]]//Dimensions

bKompl=dataKomp[[3;;,{-2,-1}]];
v1=bKompl.{1,I};
bKompl/.{a_Real,b_}:>a+I*b;
#.{1,I}&/@bKompl;

pŘÍLIŠ ŽLUŤOUČKÝ Kůň úpěl ďábelské ódy

(*tady pisu co chci*)
AmatRe=dataKomp[[3;;,1;;-3;;2]];
AmatIm=dataKomp[[3;;,2;;-3;;2]];
LinearSolve[AmatRe+I*AmatIm,v1]

dataKomp//Dimensions

{a,d,c}*2

Times[a,d]

sol=y[t]/.NDSolve[{y''[t]
+11y'[t]+2y[t]==((Sin[t])/(t+1)),y[0]==1,y'[0]==5},y[t],{t,0,100}][[1,1]]

MatrixPower[{{1,2},{7,13}},(1/5.)]

Plot[sol,{t,0,100},PlotRange->All]

f=x+2y;
podm=(x^2)+(y^2)-1;
lagrange=f+λ*podm;
0==D[lagrange,#]&/@{x,y,λ}
Solve[%]//N

FindMinimum[{f,podm==0},{x,y}]

Minimize[{f,podm==0},{x,y}]

FindMaximum[{f,podm==0},{x,y}]

FileNames[]

teploty=Import["teploty.xls"][[1]]//Flatten;
ListPlot[teploty]

vykon[t_]:=20/;-Infinity<t≤-15
vykon[t_]:=15/;-15<t≤-12
vykon[t_]:=12/;-12<t≤-8
vykon[t_]:=9/;-8<t≤-2
vykon[t_]:=5/;-2<t≤5
vykon[t_]:=3/;5<t≤13
vykon[t_]:=0/;13<t≤Infinity

Plot[vykon[t],{t,-20,20}]

cas=Table[3600*i,{i,0,Length[teploty]-1}];

{cas,vykon/@teploty}//Transpose;

dvojice=
Table[{cas[[i]],vykon[teploty[[i]]]},{i,1,Length[teploty]}];

Thread[{cas,vykon/@teploty}]

intVykony=Interpolation[dvojice,InterpolationOrder->0]

Quiet@NIntegrate[intVykony[t],{t,0,cas[[-1]]}]

7.230282013017038`*^7

dataproud=Import["DataStatistika.xls"][[1]]//Flatten;

StandardDeviation[dataproud]

Mean[dataproud]

Variance[dataproud]