[求助]S函数中能否调用M函数

我现在写了一个S-FUNCTION

里面调用了一些M函数，当把S函数的名字写入S—FUNCTION块的时候

总是出现

??? SWITCH expression must be a scalar or string constant.

Error in ==> HSV at 32

switch flag,

不知道该如何处理了，请教大家了

AreaCXJTFT等都为M函数，如果我调用方式出现错误，请指出阿，:biggrin: :biggrin:

程序如下：

看着很麻烦，其实就是判断区域Area后，根据Area的值选择输出的计算方式:

function [sys,x0,str,ts]=HSV(t,x,u,flag)

switch flag,

case 0

[sys,x0,str,ts] = mdlInitializeSizes; % Initialization

case 3

sys = mdlOutputs(t,x,u); % Calculate outputs

case { 1, 2, 4, 9 }

sys = []; % Unused flags

otherwise

error(['Unhandled flag = ',num2str(flag)]); % Error handling

end;

function [sys,x0,str,ts] = mdlInitializeSizes

sizes = simsizes;

sizes.NumContStates= 0;

sizes.NumDiscStates= 0;

sizes.NumOutputs=7;

sizes.NumInputs=2;

sizes.DirFeedthrough=0;

sizes.NumSampleTimes=1;

sys = simsizes(sizes);

str = [];

ts = [-1 0];

function sys = mdlOutputs(t,x,u)

P=u(1);

Tamp=u(2)+273.15;

if (273.15<=Tamp<=1073.15) &( 0.007<=P<=100)

if (273.15<=Tamp<=623.15)

Pst=Ps(Tamp);

Pb12=Pst;

if P>=Pb12

Area=1;

else

Area=2;

end

elseif (623.15

Pb23=P23(Tamp);

Pst=Ps(Tamp);

if (623.15

if P==Pst

Area=4;

elseif (Tamp==647.096)&(P==22.064)

GV=0.003106;

Area=4;

end

elseif P

Area=2;

else

Area=3

end

else (863.15<=Tamp<=1073.15)

Area=2;

end

else

return

end

switch Area,

case 1

PS=16.53; %1区基本方程3.1中压力常数，MPa

TS=1386; %1区基本方程3.1中温度常数，K

GH=1;

GS=1;

GV=1;

LH=TS*R0*(TS/Tamp)*AreaARr(P,Tamp);

LS=R0*((TS/Tamp)*AreaARr(P,Tamp) -AreaAR(P,Tamp));

LV=TS*R0*AreaARY(P,Tamp)/(PS*1000);

subArea=1;

case 2

TS=540; %TS=540K

PS=1; %PS=1Mpa

LH=1; %2_过热蒸汽区中水的比焓不计算

LS=1; %2_过热蒸汽区中水的比熵不计算

LV=1; %2_过热蒸汽区中水的比容不计算

if P<=10

GH=R0*T0*(TS/Tamp)*AreaBaH(P,Tamp);

GS=R0*AreaBaS;

GV=R0*T0*(P/PS)*AreaBaV(P,Tamp);

else

GH=R0*T0*(TS/Tamp)*AreaBaH(P,Tamp);

GS=R0*AreaBaS;

GV=R0*T0*(P/PS)*AreaBaV(P,Tamp);

end

subArea=2;

case 3

TS=647.096; %TS=647.096K

LH=1;

LS=1;

LV=1;

GH=R*TS*(AreaCTFT(P,Tamp)+AreaCDFD(P,Tamp));

GS=R*(AreaCTFT(P,Tamp)-AreaCF(P,Tamp));

GV=AreaCV(P,Tamp);

subArea=3;

case 4

LH=R*T*(AreaCNDTFT(P,Tamp)+AreaCNDDFD(P,Tamp));

LS=R*(AreaCNDTFT(P,Tamp)-AreaCNDF(P,Tamp));

LV=AreaCNDV(P,Tamp);

GH=R*T*(AreaCXJTFT(P,Tamp)+AreaCXJDFD(P,Tamp));

GS=R*(AreaCXJTFT(P,Tamp)-AreaCXJF(P,Tamp));

GV=AreaCXJV(P,Tamp);

subArea=4;

otherwise

return

end

sys=[LH,LS,LV,GH,GS,GV,subArea];