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>> DAVID J. Malan: Kama pengine kujua,
joto ni kipimo kwa kutumia

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mizani tofauti katika mbalimbali
sehemu ya dunia.

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Kwa mfano, digrii 212 Fahrenheit ni
100 digrii Celsius na digrii 32

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Fahrenheit ni 0 nyuzi.

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Je, si ni kuwa nzuri kama tulikuwa na kompyuta
mpango huo alituruhusu

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kubadili kutoka, kusema, Fahrenheit
kwa Celsius?

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>> Naam, tunaweza kuandika mpango huo.

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Hebu kwanza kuanza na ni pamoja na cs50.h,
ili tuweze kutumia kazi kuitwa

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kupata kuelea, ambayo, kama kupata int, anapata
idadi kutoka kwa mtumiaji, lakini hii a wakati

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yaliyo hatua ya simu - moja
na ya uhakika decimal.

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>> Hebu pia ni pamoja na kiwango io.h
hivyo kwamba tuna upatikanaji wa

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kazi kama magazeti f.

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Na hebu pia kutangaza kuu
katika njia ya kawaida.

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>> Hebu ijayo haraka user kwa
joto katika Fahrenheit.

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Hebu sasa kweli kupata kwamba hali ya joto
kutoka kwa mtumiaji, kwanza kwa

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kutangaza variable kuitwa
f ya aina kuelea.

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kuelea, tena, maana variable kwamba
maduka yaliyo hatua thamani,

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moja na hatua ya decimal.

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>> Hebu hawawajui kurudi
thamani ya kupata kuelea.

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Na kisha hebu kufanya kidogo ya hesabu
juu yake, kwanza kutangaza kuelea mwingine

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aitwaye C kwa Celsius na kuhifadhi katika C
matokeo ya baadhi ya hesabu ya kawaida.

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5.0 kugawanywa kwa mara 9.0 F minus 32.0.

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>> Hebu sasa magazeti matokeo
ya hesabu hii.

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asilimia f -

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akionyesha placeholder kwa
yaliyo hatua thamani -

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comma C magazeti nje
joto katika Celsius.

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Hebu kuokoa mwisho wangu.

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Kukusanya na F kwa C. kukimbia mpango
na dot slash F C.

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>> Na hebu jaribu wale kawaida
joto.

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Digrii 212 Fahrenheit katika
ni nyuzi 100 Celsius.

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Nyuzi 32 katika Fahrenheit ni
0 digrii katika Celsius.

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>> Sasa lets kuboresha mpango huu kidogo
kidogo na si uchapishaji kabisa kama wengi 0 ya

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baada ya kuwa mahali decimal.

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Kwa kufanya hivyo, mimi nina kwenda
kwenda nyuma ya mstari wa 11.

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Na badala ya kutaja asilimia f,
Mimi nina kwenda badala bayana, kusema,

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0.1 f, taarifa magazeti f kwamba mimi tu
unataka magazeti yaliyo hatua thamani

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kwa thamani moja baada ya mahali decimal.

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>> Hebu resave mpango wangu.

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Recompile ni pamoja na kufanya F C. Kisha
rerun ni pamoja na dot slash F C. Na

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hebu jaribu tena na, kusema, 212,
ambayo inatoa mimi 100.0.

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>> Sasa ni thamani kubainisha kwamba mimi
kitu kwa makusudi sana katika line 9.

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Taarifa jinsi niliandika 5 ni 5.0, 9
kama 9.0, na hata 32 kama 32.0.

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Naam, kwanza wawili wa maadili hayo walikuwa
sana kwa makusudi amechaguliwa kuwa

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maadili yaliyo uhakika, si kwa sababu tu
ya uthabiti na wengine

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ya mpango wangu -

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ambayo ni wazi inahusisha yaliyo
hatua maadili -

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lakini kwa sababu zinageuka kuwa C, Kama
kugawanya int na mwingine int,

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kusababisha jibu wewe ni kwenda kupata ni
yenyewe int, hata kama njia

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kuwa na kutupa kila kitu
baada ya uhakika decimal.

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>> Kwa maneno mengine, kama mimi kubadili hali hii 5.0 kwa
5 au hii 9.0-9 na kisha resave

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mpango wangu, recompile na kufanya F C,
na kisha re-kuendesha kwa dot slash F

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kwa C na aina katika mchango wa kama 212,
taarifa kwamba jibu mimi nina kwenda

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kupata wakati huu ni kweli sawa kabisa.

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0.0 ni si shahada sahihi katika
Celsius kama 212 Fahrenheit.

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>> Naam, ni nini kinaendelea?

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Naam, katika line 9, kwa sababu 5 ni sasa
integer na kwa sababu 9 ni sasa

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integer, matokeo hesabu
lazima 0.5555 na kadhalika.

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Lakini kwa sababu matokeo, kwa mujibu wa
Sheria C, ina kuwa int, kwamba

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0.5555 anapata kutupwa mbali,
kuacha yetu na 0 tu.

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>> Hivyo katika mwisho, mimi kuishia kuzidisha
kabisa ajali 0 mara f minus

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32.0, ambayo ni bila kujali
daima kwenda nipe 0.

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Hivyo kukumbuka, wakati wowote kwa kutumia
maadili yaliyo hatua katika ukaribu wa

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ints, huenda si lazima
kupata jibu hivyo kutarajia.

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Na hivyo kuchukua huduma kwa kutumia, kama mimi katika
maadili kesi ya kwanza, floating hatua

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katika ili kuepuka masuala yoyote hayo.

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