if condition problem and positive condition

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Redwood
Redwood 2019-10-18
评论： Redwood 2019-10-19
Dear Matlab experts,
I added "if condition" in the Matlab coding.
I defined m1 = n1-ee1, and I used "if condition" because I would like to get only positive value for m1.
However, I could not get any result.
if n1 <= ee1
m1 =0;
else if n1 > ee1
m1 = n1 - ee1;
My full coding is below. Please let me know how to fix it.
Thank you very much in advance.
Sincerely yours,
J1
t = 0:.0001: 5;
z = 1819;
e1 = -42;
e2 = -7;
e3= -20;
e4= -29;
e5 = -32;
e6 = -112;
e7 = -70;
e8 = -9;
e9 = -48;
e10 = -14;
e11 = -2;
e12 = -22;
e13= -42;
e14= -15;
e15 = -26;
e16 = -58;
e17 = -24;
e18 = -73;
e19 = -102;
e20 = -78;
e21 = -600;
e22 = -11;
e23= -65;
e24= -285;
e25 = -32;
p = exp(-t.*e1) + exp(-t.*e2) + exp(-t.*e3) + exp(-t.*e4) + exp(-t.*e5) + exp(-t.*e6) + exp(-t.*e7) + exp(-t.*e8) + exp(-t.*e9) + exp(-t.*e10) + exp(-t.*e11) + exp(-t.*e12) + exp(-t.*e13) + exp(-t.*e14) + exp(-t.*e15) + exp(-t.*e16) + exp(-t.*e17) + exp(-t.*e18) + exp(-t.*e19) + exp(-t.*e20) + exp(-t.*e21) + exp(-t.*e22) + exp(-t.*e23) + exp(-t.*e24) + exp(-t.*e25) ;
b1 = (exp(-t.*e1))./p;
b2 = (exp(-t.*e2))./p;
b3 = (exp(-t.*e3))./p;
b4 = (exp(-t.*e4))./p;
b5 = (exp(-t.*e5))./p;
b6 = (exp(-t.*e6))./p;
b7 = (exp(-t.*e7))./p;
b8 = (exp(-t.*e8))./p;
b9 = (exp(-t.*e9))./p;
b10 = (exp(-t.*e10))./p;
b11 = (exp(-t.*e11))./p;
b12 = (exp(-t.*e12))./p;
b13 = (exp(-t.*e13))./p;
b14 = (exp(-t.*e14))./p;
b15 = (exp(-t.*e15))./p;
b16 = (exp(-t.*e16))./p;
b17 = (exp(-t.*e17))./p;
b18 = (exp(-t.*e18))./p;
b19 = (exp(-t.*e19))./p;
b20 = (exp(-t.*e20))./p;
b21 = (exp(-t.*e21))./p;
b22 = (exp(-t.*e22))./p;
b23 = (exp(-t.*e23))./p;
b24 = (exp(-t.*e24))./p;
b25 = (exp(-t.*e25))./p;
n1 = z*b1;
n2 = z*b2;
n3 = z*b3;
n4 = z*b4;
n5 = z*b5;
n6 = z*b6;
n7 = z*b7;
n8 = z*b8;
n9 = z*b9;
n10 = z*b10;
n11 = z*b11;
n12 = z*b12;
n13 = z*b13;
n14 = z*b14;
n15 = z*b15;
n16 = z*b16;
n17 = z*b17;
n18 = z*b18;
n19 = z*b19;
n20 = z*b20;
n21 = z*b21;
n22 = z*b22;
n23 = z*b23;
n24 = z*b24;
n25 = z*b25;
ee1 = 42;
ee2 = 7;
ee3 = 20;
ee4 = 29;
ee5 = 32;
ee6 = 112;
ee7 = 70;
ee8 = 9;
ee9 = 48;
ee10 = 14;
ee11 = 2;
ee12 = 22;
ee13 = 42;
ee14 = 15;
ee15 = 26;
ee16 = 58;
ee17 = 24;
ee18 = 73;
ee19 = 102;
ee20 = 78;
ee21 = 600;
ee22 = 11;
ee23 = 65;
ee24 = 285;
ee25 = 32;
m1 = n1 - ee1;
m2 = n2 - ee2;
m3 = n3 - ee3;
m4 = n4 - ee4;
m5 = n5 - ee5;
m6 = n6 - ee6;
m7 = n7 - ee7;
m8 = n8 - ee8;
m9 = n9 - ee9;
m10 = n10 - ee10;
m11 = n11 - ee11;
m12 = n12 - ee12;
m13 = n13 - ee13;
m14 = n14 - ee14;
m15 = n15 - ee15;
m16 = n16 - ee16;
m17 = n17 - ee17;
m18 = n18 - ee18;
m19 = n19 - ee19;
m20 = n20 - ee20;
m21 = n21 - ee21;
m22 = n22 - ee22;
m23 = n23 - ee23;
m24 = n24 - ee24;
m25 = n25 - ee25;
if n1 <= ee1
m1 =0;
else if n1 > ee1
m1 = n1 - ee1;
y = m1.*m1 + m2.*m2 + m3.*m3 + m4.*m4 + m5.*m5 + m6.*m6 + m7.*m7 + m8.*m8+ m9.*m9 + m10.*m10 +m11.*m11 + m12.*m12 + m13.*m13 + m14.*m14 + m15.*m15 + m16.*m16 + m17.*m17 + m18.*m18+ m19.*m19 + m20.*m20+ m21.*m21 + m22.*m22 + m23.*m23 + m24.*m24 + m25.*m25;
plot(t, sqrt(y))
[ymin, yi] = min(y);
tmin = t(yi)
ymin =y(yi)

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采纳的回答

Image Analyst
Image Analyst 2019-10-19
You separated the else and the if. It should be elseif (one word) but actually you don't even need it. Try this:
if n1 <= ee1
m1 = 0;
else
m1 = n1 - ee1;
end

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